Monday, May 04, 2015

More on APS statement on climate change

The APS is soliciting comments by its members on a draft statement on climate change, following up their 2007 statement.

The current draft has three sections: On Climate Change, On Climate Science, and On Climate Action. Eli has written earlier about the near-kidnapping of the process by a subcommittee stacked with several climate change deniers. Here is the draft of my suggestions. The draft was reduced in length to match APS's 3500-character limitation.
Suggestions for APS statement on climate change

Change the last sentence of the first paragraph (On Climate Change) to read….

The potential consequences of climate change are great: rising temperatures, melting polar ice caps, rising sea levels, ocean acidification, and more intense extremes of the hydrological cycle (drought and floods). Some of these consequences of anthropogenic global warming (including melting of the polar ice caps) are happening now, and will become more severe in the future. The policies of the next few decades will determine human influences on the climate for centuries.

On Climate Science

The basic ideas underlying the Greenhouse Effect have been recognized for nearly two centuries. The atmosphere is largely transparent in the visible part of the spectrum, and largely opaque in the infrared part of the spectrum. This fact, combined with the Stefan-Boltzmann law, explains why the Earth is warmer than it would be in the absence of greenhouse gases in the atmosphere. A simple calculation shows that in the absence of greenhouse gases, the earth’s surface temperature would be -18 C, colder than the freezing point of water. Instead, the Earth’s surface is +15 C, which is 33 C warmer. This naturally occurring Greenhouse Effect is a large effect, which has existed ever since the early Earth acquired a greenhouse atmosphere billions of years ago.

Since the industrial revolution two centuries ago, the burning of fossil fuels has increased the concentration of carbon dioxide in the atmosphere. This leads to an anthropogenic enhancement of the greenhouse effect and further warming. The argument is a short and simple one: burning of fossil fuels —> increased atmospheric concentration of carbon dioxide —> enhanced greenhouse effect —> modern anthropogenic global warming.

Modern climate scientists argue about the details, but not about the basic finding; i.e., whether or not anthropogenic global warming is happening at all. A useful analogy is with evolution in biology: Nearly all biologists believe in evolution. Biologists argue about the details of evolution, but not about whether or not evolution is happening at all.

A crucial question is whether or not modern anthropogenic global warming will cause a temperature rise that is large enough to cause a problem. The research, summarized by the IPCC, has asked what temperature rise would result from a doubling of carbon dioxide levels in the atmosphere compared with preindustrial levels. Estimates center on a temperature rise of 3 C. While this result is calculated by computer modeling, it agrees with estimates using the sensitivity of the earth’s climate, as measured using the empirical data from the Earth’s warming at the end of the ice ages. This enhances confidence in the computer models.

A temperature rise of 3 C will be enough to melt the polar icecaps. Indeed the polar icecaps are starting to melt already.

On Climate Action

Atmospheric carbon dioxide levels are currently 400 ppm, 43% higher than the preindustrial level of 280 ppm. A level of twice the preindustrial level (560 ppm) will be reached within a few decades if current trends continue. The situation is urgent because increased carbon dioxide concentrations persist in the atmosphere for centuries.

After the current final sentence:

The APS further urges physicists to collaborate with colleagues across disciplines in climate research and to contribute to the public dialogue.

Add the following…
The APS is not acting in isolation, as shown by the 36 science academies from countries or regions around the world that have issued statements accepting global warming.

These include: Australia, Belgium, Brazil, Cameroon, Canada, the Caribbean region, China, France, Germany, Ghana, India, Indonesia, Ireland, Italy, Japan, Kenya, Madagascar, Malaysia, Mexico, Nigeria, New Zealand, Russia, Senegal, South Africa, Sudan, Sweden, Switzerland, Tanzania, Uganda, United Kingdom, United States, Zambia and Zimbabwe.

National and international organizations from nearly every field of science have issued statements accepting global warming. No scientific organization (which excludes denier websites and front groups) has issued a statement rejecting the basic findings of human-caused global warming.

The list of over 60 organizations includes: American Academy of Pediatrics, American Association for the Advancement of Science, American Association of Petroleum Geologists, American Association of State Climatologists, American Association of Wildlife Veterinarians, American Astronomical Society, American Chemical Society, American College of Preventative Medicine, American Geological Institute, American Geophysical Union, American Institute of Physics, American Institute of Biological Scientists, American Institute of Professional Geologists, American Medical Association, American Meteorological Society, American Physical Society, American Public Health Association, American Quaternary Association, American Society for Microbiology, American Statistical Association, Arctic Climate Impact Association, Australian Coral Reef Society, Australian Institute of Physics, Australian Medical Association, Australian Meteorologic and Oceanographic Society, Canadian Federation of Earth Sciences, Canadian Foundation for Climate and Atmospheric Sciences, Canadian Meteorological and Oceanographic Society, Engineers Australia, European Academy of Sciences and Arts, European Federation of Geologists, European Geosciences Union, European Physical Society, European Science Foundation, Federation of Australian Scientific and Technological Societies, Geological Society of America, Geological Society of Australia, Geological Society of London, Institute of Biology (UK), Institute of Professional Engineers (NZ), InterAcademy Council, Intergovernmental Panel on Climate Change, International Association for Great Lakes Research, International Council of Academies of Engineering and Technological Sciences, International Council on Science, International Union for Quaternary Research, International Union of Geodesy and Geophysics, NASA’s Goddard Institute of Space Studies, National Association of Geoscience Teachers, National Center for Atmospheric Research, National Oceanic and Atmospheric Administration National Research Council, Network of African Science Academies, Pew Center on Climate Change, Polish Academy of Sciences, Royal Meteorological Society (UK), Royal Society of New Zealand, Society of American Foresters, State of the Canadian Cryosphere, The Wildlife Society (International), Union of Concerned Scientists, US Geological Survey, Woods Hole Oceanographic Institute, Woods Hole Research Center, World Federation of Public Health Associations, World Health Organization, World Meteorological Organization, World Wildlife Fund.

Reference for the science academies and professional organizations: James Lawrence Powell, The Inquisition of Climate Science, Columbia University Press, New York, 2011, reviewed by me in 2012.

25 comments:

Fernando Leanme said...

I wouldn't write a 3 deg temperature rise will melt the ice caps. There's no need to stick your neck out.

If you want to check the probability simply do the estimate for a mountain located in Antarctica starting out with zero snow cover and 560 ppm CO2 concentration. In other words, run it backwards.

Given the height of Antarctic mountains, the way the continent is isolated, the lack of winter light, and the water temperature in the Antractic circumpolar current that ice isn't about to melt. We will stop burning fuels and the planet will revert to previous conditions eventually.

Nigel Franks said...

That's also sticking your neck out. What does polar amplification do to a 3°C global anomaly? If warm water leads to the buttressing ice shelves disappearing, then glaciers can flow more easily to the sea.

Fernando Leanme said...

I'm not the APS. I can mimic a giraffe

And then there's the lack of support for the Antarctic ice disappearing. What I've read says Antarctica won't warm up that much, and it ought to get much more snowfall.

Barton Paul Levenson said...

LP: the lack of support for the Antarctic ice disappearing.

BPL: The GRACE satellites seem to disagree with you.

https://www.nasa.gov/mission_pages/Grace/news/grace20121129.html#.VUedEvlViko

Hank Roberts said...

> the Antarctic ice disappearing.
> What I've read says ....

When a giraffe decides t bury its head in the sand, it requires a really deep hole.

Keep digging.

Fernando Leanme said...

Grace data doesn't support the statement. One reason why the climate change story runs into objections and disbelief is the carelessness of scientists who aren't used to these things.

EliRabett said...


C'mon Fernando, Eli and the Bunnies RTFR, you are just trying to parse your way to confusion. There is an accelerating total mass loss for both Antarctica and Greenland. That mass is primarily being lost from specific regions does not mean that either ice cap is growing. They are shrinking.

Velicogna et al http://onlinelibrary.wiley.com/wol1/doi/10.1002/2014GL061052/full

Fernando Leanme said...

Eli, you are writing a propaganda statement. Go ahead, get the APS to use that bit about Antarctica and you will become famous as the guy who put bs in a serious document.

On the other hand you way wish to look at detailed station data, look at the model predictions, and learn a bit about the difference between the West Antarctic Peninsula and East Antarctica. I decided to pull it up before I kept bitching.

Fernando Leanme said...

Here, try staring at this for a while. Your friend Velikowski needs to go back to planets in collision.

Fernando Leanme said...

here it is

http://www.nature.com/nature/journal/v498/n7452/fig_tab/nature12238_F2.html

John Farley said...

The deniers are running around claiming that the ice in Antarctica is not melting. That's why I put in a link to the webpage of Hansen and Sato, showing that the Antarctic ice lost between 1000 and 2000 Gitatons over a decade. Follow the link and eyeball the graphs for yourself
!
And the rate of mass loss is increasing.

andthentheresphysics said...

Is Fernando really using model projections, suggestion increased snowfall in Greenland and Antarctica over the next 90 years, to argue that the measured reduction in ice sheet mass can't be happening?

Barton Paul Levenson said...

F: Grace data doesn't support the statement. One reason why the climate change story runs into objections and disbelief is the carelessness of scientists who aren't used to these things.

BPL: What part of "the mass of the Antarctic ice cap is decreasing over time" do you not understand?

Barton Paul Levenson said...

http://phys.org/news/2015-04-gravity-antarctic-ice-sheet-increasingly.html

David B. Benson said...

Look at the data for the Eemian, interglacial 2 just before the Holocene. I vaguely recall an estimate of 3 K warmer than now globally and much of the Greenland ice sheet melted. I don't recalll seeing any data regarding WAIS but East Antarctica ought to be safe enough.

Tom said...

There are about 150 million gigatonnes of ice in the Antarctic ice sheet.

BBD said...

Fernando

On the other hand you way wish to look at detailed station data, look at the model predictions, and learn a bit about the difference between the West Antarctic Peninsula and East Antarctica. I decided to pull it up before I kept bitching.

Wrong, as ever. See McMillan et al. (2014).

The latest Cryosat data now show ice mass loss on *both* the WAIS and the EAIS and the Antarctic Peninsula: 134 billion tonnes, 3 billion tonnes, and 23 billion tonnes of ice per year, respectively.

Please stop the constant bullshitting.

BBD said...

David B. Benson

Look at the data for the Eemian, interglacial 2 just before the Holocene. I vaguely recall an estimate of 3 K warmer than now globally and much of the Greenland ice sheet melted. I don't recalll seeing any data regarding WAIS but East Antarctica ought to be safe enough.

The Eemian was 1C - 2C warmer (GAT) than the Holocene (Hansen & Sato 2012)with ~6m MSL highstand. Latest thinking is that ~2m came from the GrIS, which melted less than previously thought (Dahl-Jensen et al. 2013; Colville et al. 2011), with the rest from a substantial collapse of the WAIS. There may also have been a contribution from sectors of the EAIS which are far from as stable as previously thought (Mengel & Levermann 2014).

David B. Benson said...

BBD --- Thank you.

coby said...

And when bringing up the Eemian let's not forget two very important things: 1. CO2 levels were nowhere near double preindustrial levels and 2. (not unrelated) 3oC for a CO2 doubling represents fast feed backs only. Whatever slow feed backs brought CO2 out of the woodwork as the world warmed up to 120K ybp before (deep ocean circulation, permafrost melt, clathrate release, a bit of it all...) will more likely than not happen again. And the slow feedback of albedo changes as large ice sheets melt will happen in the mystical and ignored post 2100 AD years.

I am very comfortable predicting the eventual total loss of Greenland and WAIS absent a negative CO2 emissions trajectory. And I struggle to see why EAIS won't follow.

Jonathan Campbell said...
This comment has been removed by the author.
Susan Anderson said...

I suspect several mildly misspelled as well as off topic comments are phishing or viruses. Don't click on the links.

Susan Anderson said...

Just click on "said" after the name and FL and any other spreaders of waste will magically reduce.

EliRabett said...

Killed em off. Thanks for noticing

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