climate – The Front Page

State of the Climate: It’s All Connected

August 12, 2020

SOCcover2 Despite the rapid pace of writing, editing, and reviewing, this is obviously not the first (or last) assessment of 2019’s climate. So we still often get asked—why now? Why release in August 2020 a comprehensive, validated check-up on the health of our planet’s climate in 2019 August, instead of in January, when it’s still hot news?

Co-editor Jessica Blunden of NOAA addressed the question a number of years ago, with a helpful look behind the scenes of State of the Climate. You can appreciate, first of all, the amazing job she and coeditor Deke Arndt (also of NOAA) do to pull this all together so fast—they’re coordinating the work of more than 500 authors and chapter editors from 61 different countries. So naturally, at first glance, churning out this report in only a matter of months is a managerial triumph–a testament to international cooperation:

The production of this document really does “take a village”; without the dedication and hard work of every single one of the people who contribute to this process, the quality and scope of the report would not be possible. Each year the number of authors tends to increase as we add new information to the report.

SOCauthormap2 In just the past decade alone Blunden and Arndt have added 150 authors and 13 additional countries. Why so many authors?

The authors are asked to contribute based on their expertise in a specific field. For our Regional Climates chapter, which is comprised of annual summaries for countries around the world, the authors are often affiliated with a specific country’s official meteorological/hydrological agency and provide analysis based on data from that agency. it’s not just any process of coordination. State of the Climate is an elaborate scheme to make a scientifically worthwhile document:

The development of the report is quite rigorous, with writing, two major peer-review processes, technical editing, layout, and approval. After the calendar year has ended, authors are given about six weeks to develop their content and provide an initial draft that is reviewed by the chapter editors.

Then the chapter editor has the draft reviewed by two or three scientists with expert knowledge in that field. Generally, we allow one to two weeks for this review to be completed and another one to two weeks for the authors to make revisions, as needed, and for the chapter editors to prepare the new version for a formal, external review.

The external review process involves anonymous peer reviews, and BAMS allows three weeks for these reviews to be completed. The authors and chapter editors then have two weeks to make revisions based on these comments and submit the final draft for approval.

Then there’s editing and layout and so on . . . as Blunden summarizes:

This document takes the time to provide the most accurate information available on the state of the climate system.

But the time isn’t actually about writing and reviewing; it’s the comprehensiveness of 429 pages and a bazillion references (no, we didn’t count them). A report that started as a 30-pager gets bigger and more precise with each iteration, because the value increases:

The longer a data record is and the larger the area it covers, the more useful it is for putting a particular climate indicator into context, for example comparing one year to another, or detecting trends over time. Today we are fortunate to have technologies and capabilities that were not available to us decades ago, such as satellite observations, but to use all those observations for climate research means combining observations from multiple sources into a single, seamless climate data record, which is neither fast nor easy.

With both satellite and direct observations, it is important to reconcile data discrepancies and inaccuracies so that the climate records are correct, complete, and comparable, and this painstaking process can take years. For our report, a high-quality dataset is ready for inclusion only after its development processes and methodologies have been scrutinized through peer review with published results. That way readers of the State of the Climate reports can depend on detailed journal articles if they want to understand the details of a data record.

The process of creating a climate quality data set and then having it evaluated by other scientists through peer review is so challenging, no more than a few are added to the State of the Climate report each year.

As Deke Arndt explains about Earth’s climate (in a webinar to watch before using State of the Climate): “If the Earth didn’t spin, and we didn’t have day and night, it would be very simple.”

That sums up the reason the State of the Climate is not simple . . . or small, or fast. It is all connected.

State of the Climate: It's All Connected

August 12, 2020

Today’s publication of State of the Climate in 2019 marks the 30^th annual release in this series of supplements to the Bulletin of the American Meteorological Society. The report is not just a service for immediate use as the latest status report on climate. It’s a resource that people worldwide will use throughout the year, and indeed as a reference through the coming years. The report, now online only, is meant to stand a test of time as a bedrock of other reports and decisions.
SOCcover2 Despite the rapid pace of writing, editing, and reviewing, this is obviously not the first (or last) assessment of 2019’s climate. So we still often get asked—why now? Why release in August 2020 a comprehensive, validated check-up on the health of our planet’s climate in 2019 August, instead of in January, when it’s still hot news?
Co-editor Jessica Blunden of NOAA addressed the question a number of years ago, with a helpful look behind the scenes of State of the Climate. You can appreciate, first of all, the amazing job she and coeditor Deke Arndt (also of NOAA) do to pull this all together so fast—they’re coordinating the work of more than 500 authors and chapter editors from 61 different countries. So naturally, at first glance, churning out this report in only a matter of months is a managerial triumph–a testament to international cooperation:

The production of this document really does “take a village”; without the dedication and hard work of every single one of the people who contribute to this process, the quality and scope of the report would not be possible. Each year the number of authors tends to increase as we add new information to the report.

SOCauthormap2 In just the past decade alone Blunden and Arndt have added 150 authors and 13 additional countries. Why so many authors?

The authors are asked to contribute based on their expertise in a specific field. For our Regional Climates chapter, which is comprised of annual summaries for countries around the world, the authors are often affiliated with a specific country’s official meteorological/hydrological agency and provide analysis based on data from that agency. it’s not just any process of coordination. State of the Climate is an elaborate scheme to make a scientifically worthwhile document:

The development of the report is quite rigorous, with writing, two major peer-review processes, technical editing, layout, and approval. After the calendar year has ended, authors are given about six weeks to develop their content and provide an initial draft that is reviewed by the chapter editors.
Then the chapter editor has the draft reviewed by two or three scientists with expert knowledge in that field. Generally, we allow one to two weeks for this review to be completed and another one to two weeks for the authors to make revisions, as needed, and for the chapter editors to prepare the new version for a formal, external review.
The external review process involves anonymous peer reviews, and BAMS allows three weeks for these reviews to be completed. The authors and chapter editors then have two weeks to make revisions based on these comments and submit the final draft for approval.

Then there’s editing and layout and so on . . . as Blunden summarizes:

This document takes the time to provide the most accurate information available on the state of the climate system.

The longer a data record is and the larger the area it covers, the more useful it is for putting a particular climate indicator into context, for example comparing one year to another, or detecting trends over time. Today we are fortunate to have technologies and capabilities that were not available to us decades ago, such as satellite observations, but to use all those observations for climate research means combining observations from multiple sources into a single, seamless climate data record, which is neither fast nor easy.
With both satellite and direct observations, it is important to reconcile data discrepancies and inaccuracies so that the climate records are correct, complete, and comparable, and this painstaking process can take years. For our report, a high-quality dataset is ready for inclusion only after its development processes and methodologies have been scrutinized through peer review with published results. That way readers of the State of the Climate reports can depend on detailed journal articles if they want to understand the details of a data record.
The process of creating a climate quality data set and then having it evaluated by other scientists through peer review is so challenging, no more than a few are added to the State of the Climate report each year.

So the State of Climate is a testament to a complex process, with complex, interrelated data sources that cry out for the reconciliation and comparison that makes the report unique. And of course, all about a climate that is nothing if not the paragon of complexity.
As Deke Arndt explains about Earth’s climate (in a webinar to watch before using State of the Climate): “If the Earth didn’t spin, and we didn’t have day and night, it would be very simple.”
That sums up the reason the State of the Climate is not simple . . . or small, or fast. It is all connected.

Future Hurricanes a Bit Stronger and Slower, but Much Wetter in a Warmer Climate

June 1, 2018

It’s been more than 8 months. Since Maria. Irma before. And Harvey before that. For many who endured them, it was yesterday. And here we are at the start of another hurricane season.
2018-NOAA-hurricane-numbers What can we expect? It is nearly indisputable that there will be hurricanes. NOAA’s forecast issued last week calls for 5-9 of them this year. Will they strike land? Science can’t yet say whether any hurricanes and tropical storms will or won’t later this season. It depends on atmospheric steering currents in the Atlantic basin and how they set up this year, particularly during the heart of the six-month season—from August through October.
But new research is looking beyond this season, beyond many seasons, and is discovering a different type of hurricane season less than 80 years from now, as Earth’s climate warms.
The new study published in the Journal of Climate finds that near-future hurricanes will be wetter and stronger, and they likely will move slower than before, increasing the risk of serious landfall flooding.
Scientists analyzed more than 20 recent hurricanes to determine how they might change near the end of this century, assuming an increase in global temperatures. One such hurricane—Ike from 2010, which inundated coastal Texas, killing more than 100 people and obliterating the popular Bolivar Peninsula barrier island north of Galveston, would have 13 percent stronger winds, move 17 percent slower, and be 34 percent wetter in a warmer world.
Others might move faster and be slightly weaker. But none of the storms reanimated in the future became drier.
“Our research suggests that future hurricanes could drop significantly more rain,” says NCAR scientist Ethan Gutmann, who led the study. Hurricane Harvey unloaded three to four feet of rain in a wide swath from Victoria, Texas, across the Houston area and into Port Arthur in extreme eastern Texas, breaking records and causing devastating flooding, and demonstrating “just how dangerous that can be,” Gutmann says.
That danger is being magnified as coastal populations continue to exponentially grow. “The potential influence of climate change on hurricanes has significant implications for public safety and the economy,” NCAR stated in a release about the new research. The study showed that “the number of strong hurricanes, as a percent of total hurricanes each year, may increase,” Ed Bensman, an NSF program director in the Division of Atmospheric and Geospace Sciences, says. “With increased development along coastlines, that has important implications for future storm damage.”
NSF supported the study, which viewed future hurricanes for the first time collectively at high resolution. Past studies looking at how hurricanes may change in a warmer climate have relied on climate model projections that are determined on a global scale and with temporal resolution of decades to centuries. Their resolution is too low to “see” future hurricanes. Weather models, on the other hand, can see them, but they aren’t used to see long-term because of the high costs of running them.
With the new research, scientists made use of an enormous NCAR dataset and ran the Weather Research and Forecasting (WRF) model at a high resolution (4 kilometers, or about 2.5 miles) focused on the lower 48 United States for two 13-year periods. The first determined the weather as it happened between 2000 and 2013 and the second simulated the same weather but with a climate 5° C (9° F) hotter and subsequently wetter that was warmed near the end of this century by unabated greenhouse gas emissions.
Comparing 22 historic Atlantic hurricanes to the same number of future hurricanes with very similar tracks found a collective 6 percent increase in top wind speeds, but a 24 percent increase in average rain rates. The future storms moved 9 percent slower than in the past.
Individually, each hurricane was unique, some changing one way and others differently. All were rainier. And while other studies have suggested that increases in atmospheric stability and wind shear may lower the total number of annual hurricanes and tropical storms, “from this study we get an idea of what we can expect from the storms that do form,” Gutmann says, and they are likely to be more intense.
2018-Hurricane-names There isn’t a way to tell yet what this year’s hurricanes will be like. But it’s another year into our warming world, and this is yet another study pointing to ominous changes with hurricanes in our future.

Withdrawal from the Paris Agreement Flouts the Climate Risks

June 2, 2017

by Keith Seitter, AMS Executive Director
President Trump’s speech announcing the U.S. withdrawal from the Paris Climate Agreement emphasizes his assessment of the domestic economic risks of making commitments to climate action. In doing so the President plainly ignores so many other components of the risk calculus that went into the treaty in the first place.
There are, of course, political risks, such as damaging our nation’s diplomatic prestige and relinquishing the benefits of leadership in global economic, environmental, or security matters. But from a scientific viewpoint, it is particularly troubling that the President’s claims cast aside the extensively studied domestic and global economic, health, and ecological risks of inaction on climate change.
President Trump put it quite bluntly: “We will see if we can make a deal that’s fair. And if we can, that’s great. And if we can’t, that’s fine.”
The science emphatically tells us that it is not fine if we can’t. The American Meteorological Society Statement on Climate Change warns that it is “imperative that society respond to a changing climate.” National policies are not enough — the Statement clearly endorses international action to ensure adaptation to, and mitigation of, the ongoing, predominately human-caused change in climate.
In his speech, the President made a clear promise “… to be the cleanest and most environmentally friendly country on Earth … to have the cleanest air … to have the cleanest water.” AMS members have worked long and hard to enable such conditions both in our country and throughout the world. We are ready to provide the scientific expertise the nation will need to realize these goals. AMS members are equally ready to provide the scientific foundation for this nation to thrive as a leader in renewable energy technology and production, as well as to prepare for, respond to, and recover from nature’s most dangerous storms, floods, droughts, and other hazards.
Environmental aspirations, however, that call on some essential scientific capabilities but ignore others are inevitably misguided. AMS members have been instrumental in producing the sound body of scientific evidence that helps characterize the risks of unchecked climate change. The range of possibilities for future climate—built upon study after study—led the AMS Statement to conclude, “Prudence dictates extreme care in accounting for our relationship with the only planet known to be capable of sustaining human life.”
This is the science-based risk calculus upon which our nation’s climate change policy should be based. It is a far more realistic, informative, and actionable perspective than the narrow accounting the President provided in the Rose Garden. It is the science that the President abandoned in his deeply troubling decision.

Policy Symposium Keynote to Focus on Tree-Climate Connnections

November 30, 2012

by Caitlin Buzzas, AMS Policy Program
The keynote speaker for the 8^th Symposium on Policy and Socio-Economic research at the AMS Annual Meeting in January will be author and journalist Jim Robbins. The Montana-based science writer for the New York Times just wrote a book on the connection between trees, forests and our atmosphere, The Man Who Planted Trees: Lost Groves, Champion Trees, and an Urgent Plan to Save the Planet.
Robbins’ talk for our meeting (Monday,7 January, 11 a.m., Room 19a) is going to span many different aspects of our annual meeting including public health, climate, and weather. The topic, “The Few Things We Know and the Many Things We Don’t about the Role of Trees and Forests on a Warmer Planet,” could be of interest to just about every topic the symposiums cover.
If you want a preview, check out his TED talk on YouTube, where Robbins’ commitment to the science of trees in climate is explained:

They say that everyone must have a child, write a book and plant a tree before they die. But for the writer and freelance journalist of the New York Times, Jim Robbins, if we just do the last part, we’d already be off to a great start. The author of “The man who planted trees” tells how he became a rooted defender when he observed the devastation of the old growth pine trees on his property in Colorado because of climate change. For him, science still hasn’t studied deep enough about these beings that filer air, stop floods, recover desert areas, purify water, block UV rays and are the basis of medicines as well as decorate the view. Much beyond shade and fresh water.

The 2013 AMS Annual Meeting actually goes a long ways toward fulfilling Robbins’ vision of discovering more about trees in our climate, with dozens of related presentations. At Monday’s poster session (2:30 p.m., Exhibit Hall 3), for example, Juliane Fry is presenting lab findings that may eventually refine regional climate mitigation policies that rely on tree plantings to produce cooling secondary aerosols. Also, as victims of fire disasters, forests feature prominently in the Weather Impacts of 2012 sessions (Tuesday, 8 January, Ballroom E). Similarly, on Wednesday (2:30 p.m., Exhibit Hall 3) Anthony Bedel will present a poster on the connection between changing climate and increasing potential for forest fires in the the Southeast, due to thriving fire fuels.
Young scientists are also following this line of work: Sunday’s Student Conference posters (5:30 p.m., Exhibit Hall 3) include a presentation by Zeyuan Chen of Stony Brook on understanding airflow in a cherry grove to better help orchard managers save their trees from bark beetles. Another student, Meredith Dahlstrom of Metropolitan State University in Colorado, presents in the same session on interannual and decadal climate mechanisms related to fluctuations in the prodigious capacities for carbon storage in the Brazilian rainforests.

AMS Releases Revised Climate Change Statement

August 27, 2012

The American Meteorological Society today released an updated Statement on Climate Change (also available here in pdf form), replacing the 2007 version that was in effect. The informational statement is intended to provide a trustworthy, objective, and scientifically up-to-date explanation of scientific issues of concern to the public. The statement provides a brief overview of how and why global climate has changed in recent decades and will continue to change in the future. It is based on the peer-reviewed scientific literature and is consistent with the majority of current scientific understanding as expressed in assessments and reports from the Intergovernmental Panel on Climate Change, the U.S. National Academy of Sciences, and the U.S. Global Change Research Program.
“This statement is the result of hundreds of hours of work by many AMS members over the past year,” comments AMS Executive Director Keith Seitter. “It was a careful and thorough process with many stages of review, and one that included the opportunity for input from any AMS member before the draft was finalized.”
The AMS releases statements on a variety of scientific issues in the atmospheric and related sciences as a service to the public, policy makers, and the scientific community.

Small Microbes Play Big in Climate Arena

March 20, 2012

Microbes may be small, but they shouldn’t be ignored when considering global climate. According to a new colloquium report from The American Academy of Microbiology, microbes such as bacteria, algae, and fungi play a powerful role in the Earth’s climate. “Incorporating Microbial Processes into Climate Models” notes how the impact of microbes on the atmosphere goes way back in time. The critical mix of carbon dioxide and oxygen we take for granted as sustaining life on the planet is due to the rise of these tiny creatures eons ago.
So what specifically do these minute forms of life have to do with climate today? According to the report, the answer is plenty. “The sum total of their activity is enormous. But of course not all microbes are the same—some of them are producing oxygen, others are consuming it. Some are taking carbon dioxide out of the air, others are adding it.”
The big questions that the report asks and plans to address by incorporating microbial processes into climate change models: what’s the overall effect of microbial activities on the concentration of carbon dioxide in the atmosphere? Is it possible this activity will absorb the carbon dioxide being added to the atmosphere? Or will the rising global temperature might spur microbes to produce even more carbon dioxide?
The authors recognize that the gap between the climatology and microbiology is large, but they say it is not insurmountable. Some of the same technologies used to collect data for climate models—satellite imaging of cloud cover and precipitation, submarine cables that monitor changes in temperature and salinity, sensors to retrieve real-time data from remote locations—can also be applied to measuring biological phenomena. Collaboration between the sciences, they believe, will benefit both fields.
A more detailed look at the report is available here.

Upping the Ante on Modeling Climate Change Impacts

March 9, 2012

There is a growing urgency to produce global projections of how a warming climate could affect life on Earth.
“Impact research is lagging behind physical climate sciences,” says Pavel Kabat, director of the International Institute for Applied Systems Analysis (IIASA) in Austria. “Impact models have never been global, and their output is often sketchy. It is a matter of responsibility to society that we do better.”
Time is running out for researchers hoping to contribute impact simulations to the IPCC’s Fifth Assessment Report (scheduled for publication in 2014). So last month, the IIASA and the Potsdam Institute for Climate Impact Research (PIK) started a project to compare climate-impact models collected from more than two dozen research groups in eight countries. The Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) will integrate climate data from state-of-the-art models, using a range of greenhouse-gas emission scenarios (models used in the project can be found here). Because the various emissions scenarios result in a range of projected global temperature increases, potential impacts also can vary widely across a range of scenarios. It is hoped that the project will clarify systematic biases that can cause models to produce disparate results.
The models will investigate the effects of climate change on global agriculture, water supplies, vegetation, and health. Results are due by July 1, and reports on each of the four impact areas are scheduled to be completed by January of 2013. This means the data could be available for the IPCC’s next report–which “will make a real difference for the assessment process,” notes Chris Field of the Carnegie Institution for Science, cochair of IPCC Working Group II. “I greatly appreciate the initiative required to get this activity underway, and I appreciate the commitment to fast-track components that will yield results in time for inclusion in the IPCC Fifth Assessment Report.”
The ISI-MIP is scheduled to continue into 2013 and could be expanded to analyze climatic impacts on transport and energy infrastructures.

Impact Models — A model developed by PIK combined precipitation and temperature projections from 19 general circulation models to predict global vegetation loss. The results are shown in this map under two different warming scenarios.

Disaster Risk Management Meets Climate Change Adaptation

January 25, 2012

by William Hooke, AMS Policy Program Director, from the AMS project, Living on the Real World
An increasingly popular and visible feature of AMS Annual Meetings is a suite of so-called Town Halls. Often scheduled for the lunch hour (and therefore attracting primarily that minority of attendees who prefer food for thought to the competing invitation of physical sustenance with friends), these sessions are supposed to model the iconic town halls that once were the heart of the new England political process. They’re more about community input than any erudition of the speakers.

AMS Town Halls are typically used to roll out federal agency initiatives, strategic plans, and/or explore the interface between our community’s science and major developments within the policy arena. A sampling: yesterday one provided researchers a look at emerging directions for DoE’s climate and earth system modeling. Another looked at threats to the continuity of Earth observing systems – a topic frequently discussed in this blog.
I was a last-minute substitute panelist, for the panel on Risk Mitigation for Climate Adaptation and Natural Hazards. The session took its cue from a recently-released Summary for Policymakers of an IPCC Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX).
For those in the field, this special report has been required reading. Thirty pages or so of thoughtful, well-reviewed and well-documented material. [We can look forward to publication of the full document next month.] Here’s the bit that to me looks salient today: “Closer integration of disaster risk management and climate change adaptation, along with the incorporation of both into local, subnational, national, and international development policies and practices, could provide benefits at all scales.” [page 9]
The idea, in a nutshell, is that disaster risk management and climate change adaptation share much in common. The Town Hall announcement highlights the difference this way: risk management draws from history, while climate change looks to the future. The idea is the incorporating this forward-looking perspective into more traditional hazard risk management will lead to more resilient communities.
This is a great thought…but also maybe a no-brainer.
On reflection, this session also provides opportunity to reflect anew on five ways (there are undoubtedly others) we might make hazard risk management itself (and by implication, climate adaptation) more effective.
Embrace No-Adverse-Impact policies. Environmental impact statements have been with us a long time. You know the idea. When you and I contemplate construction, land use, etc., we have to assess the environmental consequences of our actions. In a similar way, we could and should assess the benefits and/or risks our plans and actions imply for community resilience.
Learn from experience. When it comes with natural hazard rsik management, we should adopt the learn-from-experience habits of aviation, as embodied in the work of the National Transportations Safety Board.
Measure progress. Hazard loss figures are noisy year-to-year and uncertain. But the discipline of continually honing our ability to estimate losses will in itself contribute to the awareness needed to motivate loss reduction when averaged over years.
Foster public-private collaboration. Such collaborations are not optional in today’s free-market societies. However, there’s considerable room for improving the level of such collaborations. They should not be fragmented, haphazard, merely tactical. They should instead be truly collaborative, ongoing, strategic.
Revitalize a venerable institution. Much has been made recently about a notional move of NOAA from the Department of Commerce into the Department of Interior. Dr. Lubchenco was questioned on this in her talk of yesterday. With NOAA embedded in Commerce, a good case can be made that the Department of Commerce provides an excellent home for achieving these several goals of hazard risk reduction and climate adaptation. However, this potential has been recognized and ignored for decades. If it’s never to be realized, then a move to Interior makes more sense.

A Good Climate for Looking at Clouds

November 17, 2010

How much do we know about clouds and the effects they have on climate change? It’s a lingering source of uncertainty, with as many questions as answers. No wonder the National Science Foundation calls them “The Wild Card of Climate Change” on its new website about the effect of clouds in climate.
The site is good place to start thinking about this complicated issue. The NSF page features videos of cloud experts like David Randall of Colorado State University and AMS President Peggy LeMone of NCAR, as well as a slide show, animations, articles, and other educational material that address some of most salient cloud/climate questions, such as: Will clouds help speed or slow climate change? Why is cloud behavior so difficult to predict? And how are scientists learning to project the behavior of clouds?
The impression one gets from the website about the progress of the science in this area may vary depending on your point of view, but Randall, for one, sounds about as optimistic as you can get. In his video, he admits that optimism is a job requirement for climate modelers, but in his assessment, “We’re not in the infant stages of understanding [clouds] any more; we’re in first or second grade, and on the way to adolescence.” His hope for solving their role in climate and representing cloud effects in climate modeling rests in part on better computers and in part on the numerous bright people entering the field now, ready to overshadow the work of their mentors.
The AMS Annual Meeting in Seattle will be a good occasion to dig deeper at the roots of Randall’s optimism and sample some of the emerging solutions to the cloud/climate relationship. For example, Andrei Sokolov and Erwan Monier of MIT will discuss the influence that adjusting cloud feedback has on climate sensitivity (Wednesday, 26 January, 11:30 a.m. in Climate Variability and Change). Basically, they’re using small adjustments to the cloud cover used to calculate surface radiation in a model to create a suite of results–an ensemble. The range of results better reflects the sensitivity of climate observed in the 20th century better than some other methods of creating ensembles, such as adjusting the model physics.
Randall says in his video that early predictions about climate change are already coming to pass and this leads to optimism that more predictions will verify well in the coming years as we scrutinize climate more and more closely. This of course presupposes sustained efforts to observe and verify. Laying the groundwork for this task–and for thus better climate models–are Stuart Evans (University of Washington) and colleagues in a study they are presenting in Seattle. According to their abstract, “Improving cloud parameterizations in large scale models hinges on understanding the statistical connection between large scale dynamics and the cloud fields they produce.” Their study focuses on the relationship between synoptic-scale dynamic patterns and cloud properties (Monday, 24 January, 11 a.m. in Climate Variability and Change). Evans et al. dig through 13 years of cloud vertical radar profiles from the US Southern Plains site of the DOE ARM program and relate it to atmospheric “states”, thus providing a metric for evaluating how well climate models relate cloudiness to radiation and other surface properties.
While Evans and colleagues use upward looking remote sensing, Joao Teixeira (JPL/Cal Tech) and coauthors look down at boundary layer cloudiness from above–using satellites. They expect to show how new methodologies with satellite data can improve the way low level clouds are parameterized in climate models (Thursday, 27 January, 9:30 a.m., in Climate Variability and Change). A recent workshop at Cal Tech on space-based studies of this problem stated:

Clouds in the boundary layer, the lowermost region of the atmosphere adjacent to the Earth’s surface, are known to play the key role in climate feedbacks that lead to these large uncertainties. Yet current climate models remain far from realistically representing the cloudy boundary layer, as they are limited by the inability to adequately represent the small-scale physical processes associated with turbulence, convection and clouds.

The lack of realism of the models at this low level is compounded by the lack of global observing of what goes on underneath the critical low-level cloud cover–hence the effort of Teixeira et al. (and others) to “leverage” satellite observing, with its global reach, to improve understanding of low level thermodynamics in the name of improving climate simulations.