Did climate scientists in the 1980s predict a 1 meter sea level rise by now?
Clash Royale CLAN TAG#URR8PPP
up vote
53
down vote
favorite
Stuart Agnew is a Member of the European Parliament for the Eastern Counties (in the UK) and stood on the UKIP ticket. His web site describes attending a global warming conference in the "mid-Eighties" at the University of East Anglia. He writes:
The highlight of the conference was a series of maps of our Norfolk coastline. The first map displayed the status quo, the second what it would look like if sea levels rose by one metre, the third five metres and the fourth ten metres. We were assured that, within 30 years, sea levels would have risen by at least one metre, probably five metres and possibly ten.
Were any climate scientists (meaning people who might reasonably have been invited to give a talk at a scientific conference) in the 1980s predicting a 1 meter sea level rise within 30 years? If so, were these predictions part of the mainstream consensus within climate science at the time?
climate-change
 |Â
show 5 more comments
up vote
53
down vote
favorite
Stuart Agnew is a Member of the European Parliament for the Eastern Counties (in the UK) and stood on the UKIP ticket. His web site describes attending a global warming conference in the "mid-Eighties" at the University of East Anglia. He writes:
The highlight of the conference was a series of maps of our Norfolk coastline. The first map displayed the status quo, the second what it would look like if sea levels rose by one metre, the third five metres and the fourth ten metres. We were assured that, within 30 years, sea levels would have risen by at least one metre, probably five metres and possibly ten.
Were any climate scientists (meaning people who might reasonably have been invited to give a talk at a scientific conference) in the 1980s predicting a 1 meter sea level rise within 30 years? If so, were these predictions part of the mainstream consensus within climate science at the time?
climate-change
18
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
11
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
16
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
4
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
3
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13
 |Â
show 5 more comments
up vote
53
down vote
favorite
up vote
53
down vote
favorite
Stuart Agnew is a Member of the European Parliament for the Eastern Counties (in the UK) and stood on the UKIP ticket. His web site describes attending a global warming conference in the "mid-Eighties" at the University of East Anglia. He writes:
The highlight of the conference was a series of maps of our Norfolk coastline. The first map displayed the status quo, the second what it would look like if sea levels rose by one metre, the third five metres and the fourth ten metres. We were assured that, within 30 years, sea levels would have risen by at least one metre, probably five metres and possibly ten.
Were any climate scientists (meaning people who might reasonably have been invited to give a talk at a scientific conference) in the 1980s predicting a 1 meter sea level rise within 30 years? If so, were these predictions part of the mainstream consensus within climate science at the time?
climate-change
Stuart Agnew is a Member of the European Parliament for the Eastern Counties (in the UK) and stood on the UKIP ticket. His web site describes attending a global warming conference in the "mid-Eighties" at the University of East Anglia. He writes:
The highlight of the conference was a series of maps of our Norfolk coastline. The first map displayed the status quo, the second what it would look like if sea levels rose by one metre, the third five metres and the fourth ten metres. We were assured that, within 30 years, sea levels would have risen by at least one metre, probably five metres and possibly ten.
Were any climate scientists (meaning people who might reasonably have been invited to give a talk at a scientific conference) in the 1980s predicting a 1 meter sea level rise within 30 years? If so, were these predictions part of the mainstream consensus within climate science at the time?
climate-change
climate-change
edited Sep 3 at 15:30
asked Sep 3 at 10:38
Paul Johnson
5,37041632
5,37041632
18
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
11
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
16
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
4
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
3
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13
 |Â
show 5 more comments
18
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
11
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
16
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
4
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
3
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13
18
18
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
11
11
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
16
16
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
4
4
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
3
3
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13
 |Â
show 5 more comments
4 Answers
4
active
oldest
votes
up vote
82
down vote
accepted
The 24 October 1983 report Projecting Future Sea Level Rise: Methodology, Estimates to the Year 2100 , 2nd edition, predicted (mid-range scenario, see table 4.1 on page 39):
by 2000:
8.8-13.2 cm
by 2025:
26.2-39.3 cm
The mid-range scenario assumed a climate sensitivity of 3.0 degrees C per doubling of CO2 concentration. The mid-range scenario was further split into two scenarios, one where rise due to net melting equaled rise due to thermal expansion, and a second where rise due to melting was twice that due to thermal expansion.
In addition to the mid-range scenarios, extreme low and high scenarios, were considered.
In the low scenario assumed was: climate sensitivity of 1.5 degrees per doubling of CO2 concentration, partial mitigation of CO2 increase due to halving the price of nuclear energy, low heat diffusivity of the ocean, low rates of increase of methane, N2O, and CFCs, low economic productivity growth, rise due to net melting equaled rise due to thermal expansion, and a constant 53% of CO2 emissions being retained in the atmosphere.
The low scenario yielded an estimated rise of 4.8cm by 2000 and 13.0cm by 2025.
In the high scenario assumed was: climate sensitivity of 4.5 degrees per doubling of CO2 concentration, high heat diffusivity of the ocean, high rates of increase of methane, N2O, and CFCs, high economic productivity growth, rise due to net melting being double rise due to thermal expansion, and an initial 60% of CO2 emissions rising to 80% being retained in the atmosphere.
The high scenario yielded an estimated rise of 17.1cm by 2000 and 54.9cm by 2025.
Actual change to 2000 was about 3cm and to present about 8cm.
So in summary, all the scenarios resulted in predictions of sea level rise of well below 1 meter by the present (2018) time. Actual rise has been slightly below the lowest of the scenarios.
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
 |Â
show 4 more comments
up vote
38
down vote
The conference would have presumably been organized by the Climate Research Unit. They have published proceedings for similar conferences going back to at least 1973. It would be ideal to track down the relevant proceedings to identify the exact meeting and paper to which the quote is referring, but this would require some library research.
How about other sources on the science in general as of the mid-1980s? Here is a report from 1983 which accepts a projection (on p. 2) of a 10 cm sea level rise over 25 years. And here is a journal article from 1987 which states (on p. 17):
Available estimates generally imply a rise on the order of one meter
in the next century.
This is much less than one meter in 30 years. So clearly, while Agnew's statement may or may not be an accurate description of one particular research presentation about Norfolk, it does not represent the scientific consensus of the mid-1980s for global sea level rise projections.
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
 |Â
show 10 more comments
up vote
6
down vote
To add to DavePhD's answer, the High range prediction was 17.1cm in 2000 and 54.9 cm in 2025.
Also, from the page following the one he cites:
AN ALTERNATIVE METHOD PRODUCES SIMILAR ESTIMATES OF SEA LEVEL RISE
To cross check our projections, we estimated sea level changes by another
method: extrapolating past associations between temperature and sea
level. Sea level rise in the last century has been estimated at 10 to
15 cm (4 to 6 inches). The surface temperature rise for the same period
has been estimated at 0.4C. Thus, the ratio of sea level rise to
temperature is somewhere between 25 and 37 cm for each degree.
Including the effects of trace gases, global warming should be
equivalent to at least a quadrupling of CO2 by 2100, which would
raise surface air temperatures by 3.0C to 9.0C (based on the National
Academy of Sciences' range for climate sensitivity, ignoring delays
caused by the heat absorbing-capacities of the oceans). using the 25
cm to 27 cm ratio for the 3C to 9C range yields sea level rises of 75
cm to 333 cm. These estimates are in line with those produced by our
more elaborate approach.
If I'm reading correctly, that 75-333cm range is for 2100, but I'm not sure. This may be the source of the quote, though.
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
add a comment |Â
up vote
1
down vote
I emailed Stuart Agnew to ask for more information. He forwarded my email to Rev. Philip Foster, who has provided this piece of evidence from "People" magazine on 8th October 1979. It features Dr Gordon MacDonald apparently predicting a sea level rise of 2 meters by 2030.
However what Dr MacDonald actually said in his Congressional Testimony is considerably tamer than this headline (see page 101 in the linked document). After emphasizing how little was known about the way in which sea temperatures would affect the West Antarctic Ice Sheet (WAIS), he suggests that once the sea temperature rose the WAIS could then shed 1/3 to 1/2 its mass over 100 years (my emphasis), and that complete melting of the WAIS would cause a 5 meter sea level rise. Presumably this is where the headline writer got the "up to here" bit. Nothing in Dr MacDonald's testimony suggests that this would happen by 2030.
Update
DavePhd has located the original People article on line. The article describes a "disaster movie" scenario "early in the 21st century" where increasing CO2 leads to temperature rises of up to 20 degrees Fahrenheit and a 20 foot sea level rise. However the article is ambiguous: its not clear whether "early in the 21st century" refers to just the CO2 increase or to the effects.
At the end of the article there is also a quote about world catastrophe "not 200 years from now but within our lifetime". Again the article is unclear, but this seems to have been a quote from an Energy Committee staffer rather than MacDonald.
Update 2
I emailed University of East Anglia to see if they had any records of Stuart Agnew attending a conference. They took it as an Freedom Of Information Act request but they didn't have any records back that far. Not surprising, but it was worth a try.
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
add a comment |Â
4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
82
down vote
accepted
The 24 October 1983 report Projecting Future Sea Level Rise: Methodology, Estimates to the Year 2100 , 2nd edition, predicted (mid-range scenario, see table 4.1 on page 39):
by 2000:
8.8-13.2 cm
by 2025:
26.2-39.3 cm
The mid-range scenario assumed a climate sensitivity of 3.0 degrees C per doubling of CO2 concentration. The mid-range scenario was further split into two scenarios, one where rise due to net melting equaled rise due to thermal expansion, and a second where rise due to melting was twice that due to thermal expansion.
In addition to the mid-range scenarios, extreme low and high scenarios, were considered.
In the low scenario assumed was: climate sensitivity of 1.5 degrees per doubling of CO2 concentration, partial mitigation of CO2 increase due to halving the price of nuclear energy, low heat diffusivity of the ocean, low rates of increase of methane, N2O, and CFCs, low economic productivity growth, rise due to net melting equaled rise due to thermal expansion, and a constant 53% of CO2 emissions being retained in the atmosphere.
The low scenario yielded an estimated rise of 4.8cm by 2000 and 13.0cm by 2025.
In the high scenario assumed was: climate sensitivity of 4.5 degrees per doubling of CO2 concentration, high heat diffusivity of the ocean, high rates of increase of methane, N2O, and CFCs, high economic productivity growth, rise due to net melting being double rise due to thermal expansion, and an initial 60% of CO2 emissions rising to 80% being retained in the atmosphere.
The high scenario yielded an estimated rise of 17.1cm by 2000 and 54.9cm by 2025.
Actual change to 2000 was about 3cm and to present about 8cm.
So in summary, all the scenarios resulted in predictions of sea level rise of well below 1 meter by the present (2018) time. Actual rise has been slightly below the lowest of the scenarios.
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
 |Â
show 4 more comments
up vote
82
down vote
accepted
The 24 October 1983 report Projecting Future Sea Level Rise: Methodology, Estimates to the Year 2100 , 2nd edition, predicted (mid-range scenario, see table 4.1 on page 39):
by 2000:
8.8-13.2 cm
by 2025:
26.2-39.3 cm
The mid-range scenario assumed a climate sensitivity of 3.0 degrees C per doubling of CO2 concentration. The mid-range scenario was further split into two scenarios, one where rise due to net melting equaled rise due to thermal expansion, and a second where rise due to melting was twice that due to thermal expansion.
In addition to the mid-range scenarios, extreme low and high scenarios, were considered.
In the low scenario assumed was: climate sensitivity of 1.5 degrees per doubling of CO2 concentration, partial mitigation of CO2 increase due to halving the price of nuclear energy, low heat diffusivity of the ocean, low rates of increase of methane, N2O, and CFCs, low economic productivity growth, rise due to net melting equaled rise due to thermal expansion, and a constant 53% of CO2 emissions being retained in the atmosphere.
The low scenario yielded an estimated rise of 4.8cm by 2000 and 13.0cm by 2025.
In the high scenario assumed was: climate sensitivity of 4.5 degrees per doubling of CO2 concentration, high heat diffusivity of the ocean, high rates of increase of methane, N2O, and CFCs, high economic productivity growth, rise due to net melting being double rise due to thermal expansion, and an initial 60% of CO2 emissions rising to 80% being retained in the atmosphere.
The high scenario yielded an estimated rise of 17.1cm by 2000 and 54.9cm by 2025.
Actual change to 2000 was about 3cm and to present about 8cm.
So in summary, all the scenarios resulted in predictions of sea level rise of well below 1 meter by the present (2018) time. Actual rise has been slightly below the lowest of the scenarios.
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
 |Â
show 4 more comments
up vote
82
down vote
accepted
up vote
82
down vote
accepted
The 24 October 1983 report Projecting Future Sea Level Rise: Methodology, Estimates to the Year 2100 , 2nd edition, predicted (mid-range scenario, see table 4.1 on page 39):
by 2000:
8.8-13.2 cm
by 2025:
26.2-39.3 cm
The mid-range scenario assumed a climate sensitivity of 3.0 degrees C per doubling of CO2 concentration. The mid-range scenario was further split into two scenarios, one where rise due to net melting equaled rise due to thermal expansion, and a second where rise due to melting was twice that due to thermal expansion.
In addition to the mid-range scenarios, extreme low and high scenarios, were considered.
In the low scenario assumed was: climate sensitivity of 1.5 degrees per doubling of CO2 concentration, partial mitigation of CO2 increase due to halving the price of nuclear energy, low heat diffusivity of the ocean, low rates of increase of methane, N2O, and CFCs, low economic productivity growth, rise due to net melting equaled rise due to thermal expansion, and a constant 53% of CO2 emissions being retained in the atmosphere.
The low scenario yielded an estimated rise of 4.8cm by 2000 and 13.0cm by 2025.
In the high scenario assumed was: climate sensitivity of 4.5 degrees per doubling of CO2 concentration, high heat diffusivity of the ocean, high rates of increase of methane, N2O, and CFCs, high economic productivity growth, rise due to net melting being double rise due to thermal expansion, and an initial 60% of CO2 emissions rising to 80% being retained in the atmosphere.
The high scenario yielded an estimated rise of 17.1cm by 2000 and 54.9cm by 2025.
Actual change to 2000 was about 3cm and to present about 8cm.
So in summary, all the scenarios resulted in predictions of sea level rise of well below 1 meter by the present (2018) time. Actual rise has been slightly below the lowest of the scenarios.
The 24 October 1983 report Projecting Future Sea Level Rise: Methodology, Estimates to the Year 2100 , 2nd edition, predicted (mid-range scenario, see table 4.1 on page 39):
by 2000:
8.8-13.2 cm
by 2025:
26.2-39.3 cm
The mid-range scenario assumed a climate sensitivity of 3.0 degrees C per doubling of CO2 concentration. The mid-range scenario was further split into two scenarios, one where rise due to net melting equaled rise due to thermal expansion, and a second where rise due to melting was twice that due to thermal expansion.
In addition to the mid-range scenarios, extreme low and high scenarios, were considered.
In the low scenario assumed was: climate sensitivity of 1.5 degrees per doubling of CO2 concentration, partial mitigation of CO2 increase due to halving the price of nuclear energy, low heat diffusivity of the ocean, low rates of increase of methane, N2O, and CFCs, low economic productivity growth, rise due to net melting equaled rise due to thermal expansion, and a constant 53% of CO2 emissions being retained in the atmosphere.
The low scenario yielded an estimated rise of 4.8cm by 2000 and 13.0cm by 2025.
In the high scenario assumed was: climate sensitivity of 4.5 degrees per doubling of CO2 concentration, high heat diffusivity of the ocean, high rates of increase of methane, N2O, and CFCs, high economic productivity growth, rise due to net melting being double rise due to thermal expansion, and an initial 60% of CO2 emissions rising to 80% being retained in the atmosphere.
The high scenario yielded an estimated rise of 17.1cm by 2000 and 54.9cm by 2025.
Actual change to 2000 was about 3cm and to present about 8cm.
So in summary, all the scenarios resulted in predictions of sea level rise of well below 1 meter by the present (2018) time. Actual rise has been slightly below the lowest of the scenarios.
edited Sep 7 at 13:50
answered Sep 3 at 15:01
DavePhD
71.4k18309333
71.4k18309333
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
 |Â
show 4 more comments
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
22
22
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
Their prediction in the low scenario was 2.4-4.8 cm by 2000 and 6.5-13.0 cm by 2025, which makes the low scenario prediction consistent with the actual change to 2000. It also means the actual change to present is already greater than the lowest predicted change (6.5 cm) by 2025.
â called2voyage
Sep 5 at 15:07
2
2
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@called2voyage I see "4.8" for 2000 and "13.0" for 2025 for the low scenario in Table 4.1 (page 39). The "2.4" and "6.5" on page 61 is for "thermal expansion only", which is only one of the components of sea level change.
â DavePhD
Sep 5 at 15:14
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
@DavePhD Good catch. That said, 4.8 cm is still not far off from 3 cm, and 8 cm at present could be on track for 13.0 cm by 2025.
â called2voyage
Sep 5 at 15:26
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
I don't understand why this particular report is being singled out? It isn't an example of someone claiming a 1 meter sea level rise by 2015...
â aquirdturtle
Sep 5 at 16:15
5
5
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
@aquirdturtle this was a very prominent report in the field. It is to show that significantly less than a meter was expected. See table IV here link.springer.com/article/10.1007/BF01901630 for a compilation of 1980s future sea level predictions if you what to see more.
â DavePhD
Sep 5 at 16:17
 |Â
show 4 more comments
up vote
38
down vote
The conference would have presumably been organized by the Climate Research Unit. They have published proceedings for similar conferences going back to at least 1973. It would be ideal to track down the relevant proceedings to identify the exact meeting and paper to which the quote is referring, but this would require some library research.
How about other sources on the science in general as of the mid-1980s? Here is a report from 1983 which accepts a projection (on p. 2) of a 10 cm sea level rise over 25 years. And here is a journal article from 1987 which states (on p. 17):
Available estimates generally imply a rise on the order of one meter
in the next century.
This is much less than one meter in 30 years. So clearly, while Agnew's statement may or may not be an accurate description of one particular research presentation about Norfolk, it does not represent the scientific consensus of the mid-1980s for global sea level rise projections.
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
 |Â
show 10 more comments
up vote
38
down vote
The conference would have presumably been organized by the Climate Research Unit. They have published proceedings for similar conferences going back to at least 1973. It would be ideal to track down the relevant proceedings to identify the exact meeting and paper to which the quote is referring, but this would require some library research.
How about other sources on the science in general as of the mid-1980s? Here is a report from 1983 which accepts a projection (on p. 2) of a 10 cm sea level rise over 25 years. And here is a journal article from 1987 which states (on p. 17):
Available estimates generally imply a rise on the order of one meter
in the next century.
This is much less than one meter in 30 years. So clearly, while Agnew's statement may or may not be an accurate description of one particular research presentation about Norfolk, it does not represent the scientific consensus of the mid-1980s for global sea level rise projections.
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
 |Â
show 10 more comments
up vote
38
down vote
up vote
38
down vote
The conference would have presumably been organized by the Climate Research Unit. They have published proceedings for similar conferences going back to at least 1973. It would be ideal to track down the relevant proceedings to identify the exact meeting and paper to which the quote is referring, but this would require some library research.
How about other sources on the science in general as of the mid-1980s? Here is a report from 1983 which accepts a projection (on p. 2) of a 10 cm sea level rise over 25 years. And here is a journal article from 1987 which states (on p. 17):
Available estimates generally imply a rise on the order of one meter
in the next century.
This is much less than one meter in 30 years. So clearly, while Agnew's statement may or may not be an accurate description of one particular research presentation about Norfolk, it does not represent the scientific consensus of the mid-1980s for global sea level rise projections.
The conference would have presumably been organized by the Climate Research Unit. They have published proceedings for similar conferences going back to at least 1973. It would be ideal to track down the relevant proceedings to identify the exact meeting and paper to which the quote is referring, but this would require some library research.
How about other sources on the science in general as of the mid-1980s? Here is a report from 1983 which accepts a projection (on p. 2) of a 10 cm sea level rise over 25 years. And here is a journal article from 1987 which states (on p. 17):
Available estimates generally imply a rise on the order of one meter
in the next century.
This is much less than one meter in 30 years. So clearly, while Agnew's statement may or may not be an accurate description of one particular research presentation about Norfolk, it does not represent the scientific consensus of the mid-1980s for global sea level rise projections.
edited Sep 4 at 10:19
answered Sep 3 at 14:30
Brian Z
2,112713
2,112713
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
 |Â
show 10 more comments
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
2
2
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
A NOAA chart shows about 15cm rise since 1950.
â Daniel R Hicks
Sep 3 at 14:51
1
1
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
The proceedings wouldn't give a definitive answer to the question. People often include "breaking news" or other material in their presentations that isn't reflected in the proceedings, which are typically written months in advance.
â David Richerby
Sep 3 at 16:02
1
1
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
@DavePhD, I made a correction and replaced the material referred to in your comment.
â Brian Z
Sep 3 at 16:19
2
2
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
@DavidRicherby I don't know what field you are from, but in mine, you write the proceedings after the presentations have been given, unless you include only the abstracts sent before the conference to receive admission.
â Federico
Sep 3 at 20:05
5
5
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
@Federico: In computer science (pretty far removed from climate science, I know), proceedings contain the final accepted papers that authors have supplied at least several weeks before the conference. Where paper proceedings exist in printed form, copies are distributed to attendees when they arrive at the conference arrival.
â Henning Makholm
Sep 3 at 23:56
 |Â
show 10 more comments
up vote
6
down vote
To add to DavePhD's answer, the High range prediction was 17.1cm in 2000 and 54.9 cm in 2025.
Also, from the page following the one he cites:
AN ALTERNATIVE METHOD PRODUCES SIMILAR ESTIMATES OF SEA LEVEL RISE
To cross check our projections, we estimated sea level changes by another
method: extrapolating past associations between temperature and sea
level. Sea level rise in the last century has been estimated at 10 to
15 cm (4 to 6 inches). The surface temperature rise for the same period
has been estimated at 0.4C. Thus, the ratio of sea level rise to
temperature is somewhere between 25 and 37 cm for each degree.
Including the effects of trace gases, global warming should be
equivalent to at least a quadrupling of CO2 by 2100, which would
raise surface air temperatures by 3.0C to 9.0C (based on the National
Academy of Sciences' range for climate sensitivity, ignoring delays
caused by the heat absorbing-capacities of the oceans). using the 25
cm to 27 cm ratio for the 3C to 9C range yields sea level rises of 75
cm to 333 cm. These estimates are in line with those produced by our
more elaborate approach.
If I'm reading correctly, that 75-333cm range is for 2100, but I'm not sure. This may be the source of the quote, though.
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
add a comment |Â
up vote
6
down vote
To add to DavePhD's answer, the High range prediction was 17.1cm in 2000 and 54.9 cm in 2025.
Also, from the page following the one he cites:
AN ALTERNATIVE METHOD PRODUCES SIMILAR ESTIMATES OF SEA LEVEL RISE
To cross check our projections, we estimated sea level changes by another
method: extrapolating past associations between temperature and sea
level. Sea level rise in the last century has been estimated at 10 to
15 cm (4 to 6 inches). The surface temperature rise for the same period
has been estimated at 0.4C. Thus, the ratio of sea level rise to
temperature is somewhere between 25 and 37 cm for each degree.
Including the effects of trace gases, global warming should be
equivalent to at least a quadrupling of CO2 by 2100, which would
raise surface air temperatures by 3.0C to 9.0C (based on the National
Academy of Sciences' range for climate sensitivity, ignoring delays
caused by the heat absorbing-capacities of the oceans). using the 25
cm to 27 cm ratio for the 3C to 9C range yields sea level rises of 75
cm to 333 cm. These estimates are in line with those produced by our
more elaborate approach.
If I'm reading correctly, that 75-333cm range is for 2100, but I'm not sure. This may be the source of the quote, though.
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
add a comment |Â
up vote
6
down vote
up vote
6
down vote
To add to DavePhD's answer, the High range prediction was 17.1cm in 2000 and 54.9 cm in 2025.
Also, from the page following the one he cites:
AN ALTERNATIVE METHOD PRODUCES SIMILAR ESTIMATES OF SEA LEVEL RISE
To cross check our projections, we estimated sea level changes by another
method: extrapolating past associations between temperature and sea
level. Sea level rise in the last century has been estimated at 10 to
15 cm (4 to 6 inches). The surface temperature rise for the same period
has been estimated at 0.4C. Thus, the ratio of sea level rise to
temperature is somewhere between 25 and 37 cm for each degree.
Including the effects of trace gases, global warming should be
equivalent to at least a quadrupling of CO2 by 2100, which would
raise surface air temperatures by 3.0C to 9.0C (based on the National
Academy of Sciences' range for climate sensitivity, ignoring delays
caused by the heat absorbing-capacities of the oceans). using the 25
cm to 27 cm ratio for the 3C to 9C range yields sea level rises of 75
cm to 333 cm. These estimates are in line with those produced by our
more elaborate approach.
If I'm reading correctly, that 75-333cm range is for 2100, but I'm not sure. This may be the source of the quote, though.
To add to DavePhD's answer, the High range prediction was 17.1cm in 2000 and 54.9 cm in 2025.
Also, from the page following the one he cites:
AN ALTERNATIVE METHOD PRODUCES SIMILAR ESTIMATES OF SEA LEVEL RISE
To cross check our projections, we estimated sea level changes by another
method: extrapolating past associations between temperature and sea
level. Sea level rise in the last century has been estimated at 10 to
15 cm (4 to 6 inches). The surface temperature rise for the same period
has been estimated at 0.4C. Thus, the ratio of sea level rise to
temperature is somewhere between 25 and 37 cm for each degree.
Including the effects of trace gases, global warming should be
equivalent to at least a quadrupling of CO2 by 2100, which would
raise surface air temperatures by 3.0C to 9.0C (based on the National
Academy of Sciences' range for climate sensitivity, ignoring delays
caused by the heat absorbing-capacities of the oceans). using the 25
cm to 27 cm ratio for the 3C to 9C range yields sea level rises of 75
cm to 333 cm. These estimates are in line with those produced by our
more elaborate approach.
If I'm reading correctly, that 75-333cm range is for 2100, but I'm not sure. This may be the source of the quote, though.
answered Sep 4 at 6:08
Benjol
95911120
95911120
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
add a comment |Â
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
1
1
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
The paragraph is estimating sea level rise against temperature rise, so it is saying that a 3 degree rise would cause a sea level rise of 75cm regardless of the time frame. It is not the source of the quote because Agnew claims the estimates were in the range 1-10 meters.
â Paul Johnson
Sep 4 at 9:45
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
I'm a little suspicious of the reliability of the quote as both the projected temperature range is very high as is the projected future CO2 concentration (compared to IPCC consensus).
â matt_black
Sep 4 at 19:15
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@PaulJohnson that's presumably the final sea level rise, and even after a new stable temperature is reached the sea level will take a long time to catch up (some of the rise is due to thermal expansion, for example, and the lower ocean isn't well-coupled to the atmosphere). That's why an arbitrary date of 2100 is widely used - while not long enough for all processes stabilise, it characterises the long-term effects quite well and allows comparisons
â Chris H
Sep 5 at 11:03
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
@matt_black with an ECS range 1.5->4.5, which is around the IPCC range, a quadrupling of CO2 concentration is a total 3c to 9c rise. Those numbers are fine (although it won't happen by 2100 and they're not saying that; they're saying that's the total rise). RCP 8.5 has CO2-eq concentrations at 1200 ppm in 2100; that's a bit more than quadruple the commonly-accepted preindustrial figure of 280 ppm.
â James Picone
Sep 6 at 1:06
add a comment |Â
up vote
1
down vote
I emailed Stuart Agnew to ask for more information. He forwarded my email to Rev. Philip Foster, who has provided this piece of evidence from "People" magazine on 8th October 1979. It features Dr Gordon MacDonald apparently predicting a sea level rise of 2 meters by 2030.
However what Dr MacDonald actually said in his Congressional Testimony is considerably tamer than this headline (see page 101 in the linked document). After emphasizing how little was known about the way in which sea temperatures would affect the West Antarctic Ice Sheet (WAIS), he suggests that once the sea temperature rose the WAIS could then shed 1/3 to 1/2 its mass over 100 years (my emphasis), and that complete melting of the WAIS would cause a 5 meter sea level rise. Presumably this is where the headline writer got the "up to here" bit. Nothing in Dr MacDonald's testimony suggests that this would happen by 2030.
Update
DavePhd has located the original People article on line. The article describes a "disaster movie" scenario "early in the 21st century" where increasing CO2 leads to temperature rises of up to 20 degrees Fahrenheit and a 20 foot sea level rise. However the article is ambiguous: its not clear whether "early in the 21st century" refers to just the CO2 increase or to the effects.
At the end of the article there is also a quote about world catastrophe "not 200 years from now but within our lifetime". Again the article is unclear, but this seems to have been a quote from an Energy Committee staffer rather than MacDonald.
Update 2
I emailed University of East Anglia to see if they had any records of Stuart Agnew attending a conference. They took it as an Freedom Of Information Act request but they didn't have any records back that far. Not surprising, but it was worth a try.
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
add a comment |Â
up vote
1
down vote
I emailed Stuart Agnew to ask for more information. He forwarded my email to Rev. Philip Foster, who has provided this piece of evidence from "People" magazine on 8th October 1979. It features Dr Gordon MacDonald apparently predicting a sea level rise of 2 meters by 2030.
However what Dr MacDonald actually said in his Congressional Testimony is considerably tamer than this headline (see page 101 in the linked document). After emphasizing how little was known about the way in which sea temperatures would affect the West Antarctic Ice Sheet (WAIS), he suggests that once the sea temperature rose the WAIS could then shed 1/3 to 1/2 its mass over 100 years (my emphasis), and that complete melting of the WAIS would cause a 5 meter sea level rise. Presumably this is where the headline writer got the "up to here" bit. Nothing in Dr MacDonald's testimony suggests that this would happen by 2030.
Update
DavePhd has located the original People article on line. The article describes a "disaster movie" scenario "early in the 21st century" where increasing CO2 leads to temperature rises of up to 20 degrees Fahrenheit and a 20 foot sea level rise. However the article is ambiguous: its not clear whether "early in the 21st century" refers to just the CO2 increase or to the effects.
At the end of the article there is also a quote about world catastrophe "not 200 years from now but within our lifetime". Again the article is unclear, but this seems to have been a quote from an Energy Committee staffer rather than MacDonald.
Update 2
I emailed University of East Anglia to see if they had any records of Stuart Agnew attending a conference. They took it as an Freedom Of Information Act request but they didn't have any records back that far. Not surprising, but it was worth a try.
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
add a comment |Â
up vote
1
down vote
up vote
1
down vote
I emailed Stuart Agnew to ask for more information. He forwarded my email to Rev. Philip Foster, who has provided this piece of evidence from "People" magazine on 8th October 1979. It features Dr Gordon MacDonald apparently predicting a sea level rise of 2 meters by 2030.
However what Dr MacDonald actually said in his Congressional Testimony is considerably tamer than this headline (see page 101 in the linked document). After emphasizing how little was known about the way in which sea temperatures would affect the West Antarctic Ice Sheet (WAIS), he suggests that once the sea temperature rose the WAIS could then shed 1/3 to 1/2 its mass over 100 years (my emphasis), and that complete melting of the WAIS would cause a 5 meter sea level rise. Presumably this is where the headline writer got the "up to here" bit. Nothing in Dr MacDonald's testimony suggests that this would happen by 2030.
Update
DavePhd has located the original People article on line. The article describes a "disaster movie" scenario "early in the 21st century" where increasing CO2 leads to temperature rises of up to 20 degrees Fahrenheit and a 20 foot sea level rise. However the article is ambiguous: its not clear whether "early in the 21st century" refers to just the CO2 increase or to the effects.
At the end of the article there is also a quote about world catastrophe "not 200 years from now but within our lifetime". Again the article is unclear, but this seems to have been a quote from an Energy Committee staffer rather than MacDonald.
Update 2
I emailed University of East Anglia to see if they had any records of Stuart Agnew attending a conference. They took it as an Freedom Of Information Act request but they didn't have any records back that far. Not surprising, but it was worth a try.
I emailed Stuart Agnew to ask for more information. He forwarded my email to Rev. Philip Foster, who has provided this piece of evidence from "People" magazine on 8th October 1979. It features Dr Gordon MacDonald apparently predicting a sea level rise of 2 meters by 2030.
However what Dr MacDonald actually said in his Congressional Testimony is considerably tamer than this headline (see page 101 in the linked document). After emphasizing how little was known about the way in which sea temperatures would affect the West Antarctic Ice Sheet (WAIS), he suggests that once the sea temperature rose the WAIS could then shed 1/3 to 1/2 its mass over 100 years (my emphasis), and that complete melting of the WAIS would cause a 5 meter sea level rise. Presumably this is where the headline writer got the "up to here" bit. Nothing in Dr MacDonald's testimony suggests that this would happen by 2030.
Update
DavePhd has located the original People article on line. The article describes a "disaster movie" scenario "early in the 21st century" where increasing CO2 leads to temperature rises of up to 20 degrees Fahrenheit and a 20 foot sea level rise. However the article is ambiguous: its not clear whether "early in the 21st century" refers to just the CO2 increase or to the effects.
At the end of the article there is also a quote about world catastrophe "not 200 years from now but within our lifetime". Again the article is unclear, but this seems to have been a quote from an Energy Committee staffer rather than MacDonald.
Update 2
I emailed University of East Anglia to see if they had any records of Stuart Agnew attending a conference. They took it as an Freedom Of Information Act request but they didn't have any records back that far. Not surprising, but it was worth a try.
edited Sep 14 at 14:56
answered Sep 11 at 15:42
Paul Johnson
5,37041632
5,37041632
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
add a comment |Â
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
text of the article: "Early in the 21st century... Oceans rise everywhere by perhaps 20 feet, inundating coastal cities. Some 25 percent of the worldâÂÂs population must flee to higher ground. " people.com/archive/â¦
â DavePhD
Sep 11 at 17:13
add a comment |Â
18
I've emailed Stuart Agnew to ask if he can provide more information about who made these estimates.
â Paul Johnson
Sep 4 at 9:46
11
I've had an email conversation with both Stuart Agnew and fellow UKIPer and climate skeptic the Rev. Philip Foster. Agnew recalls the conference as being between 85 and 87, but was unable to provide any more information. Neither were able to offer any evidence of climatologists at that time predicting 1 meter or more sea level changes by now.
â Paul Johnson
Sep 4 at 19:12
16
This is tangential, but just because a prediction is wrong, doesn't mean the theory is. That's especially true in cases where the prediction is based on non-public-knowledge things (whether governments plan to adopt carbon control legislation), guesses about future culture (if 'going green' will get popular), and estimates of things that can easily change (carbon output from industry), and doesn't even account for plain ol' mistakes. Attempting to discredit the theory because the prediction is wrong is invalid.
â Nic Hartley
Sep 4 at 20:00
4
Mr. Agnew is likely putting a spin on events. I find it very hard to believe that "We were assured that ...". I think a more accurate statement would be "We were assured that, if their model was correct, ...". No credible scientist would go to a conference with predictions and claim that there is no uncertainty in their methodology.
â FGreg
Sep 4 at 20:27
3
Not a full answer, but it's worth keeping in mind that Norfolk is actually sinking (washingtonpost.com/national/health-science/â¦) at a fairly fast rate. Not sure that it explains someone claiming 1 meter, but the effective sea level rise is significantly larger in norfolk than other places.
â aquirdturtle
Sep 5 at 16:13