Presidential science adviser John Holdren and NOAA Administrator Jane Lubchenco warned of the growing impacts of climate change and the emphasized the urgency of curbing emissions and preparing for the impacts at a December 2 Congressional hearing on The State of Climate Science.  “Notwithstanding the claims of some climate-change ‘skeptics’ that climate change came to a halt over the past decade, the reality is that both the drivers and the symptoms of climate change have been growing more rapidly since 1997 than before,” Holdren told the House Select Committee on Energy Independence and Global Warming.  And: “The current state of knowledge about it (even though incomplete, as science always is) is sufficient to make clear that failure to act promptly to reduce global emissions to the atmosphere of carbon dioxide and other heat-trapping substances is overwhelmingly likely to lead to changes in climate too extreme and too damaging to be adequately addressed by any adaptation measures that can be foreseen.”

Cross-posted from the World Wildlife Fund Climate Blog, courtesy of Nick Sundt

[Sundt notes: During the hearing, the Republican members of the committee largely focused on the content of private emails among scientists that recently were stolen from a server at the Climate Research Unit at the University of East Anglia in the U.K.  The witnesses along with the Democrats on the committee responded.  We will address that element of the hearing in a separate blog posting.]

Top Administration Officials Warn Congress of Climate Change Impacts and Call for Preparedness Measures

By Nick Sundt, WWF Communications Director for Climate Change
12/03/2009
The House Select Committee on Energy Independence and Global Warming heard yesterday (2 Dec 2009) from two top Obama Administration officials who warned of the growing impacts of climate change and the emphasized the urgency of curbing emissions and preparing for the impacts.

In his opening statement [PDF] at a hearing on “The State of Climate Science,” Committee chairman Ed Markey (Democrat, Massachusetts) said that:

“Administration scientists once predicted the impacts of global warming. Now they can confirm them. And, unfortunately, families from New Orleans to Alaska are living with the harsh consequences.”

“We must be aware that as the climate system warms, we risk passing certain ‘tipping points’ of rapid and irreversible change. In the United States, the effects are evident. Daily record high temperatures are being broken twice as often as daily lows. Our farms are threatened by rising temperatures, water scarcity, and pests. In the Northeast, extreme rainstorms and the risk of flooding have increased. In Alaska, villages are finding the land they call home literally melting out from underneath them as the permafrost thaws. In the West, the shrinking mountain snowpack and increasing droughts strain our water resource systems.”

After additional opening statements from other members of the committee,  Dr. John Holdren, Director of the White House Office of Science and Technology Policy testified.  In his written testimony, Holdren methodically established that climate is changing, that “beyond any reasonable doubt” the primary cause is the buildup of greenhouse gases in the atmosphere from human activity, and that the consequences already are being felt in the U.S. and around the world.

“Notwithstanding the claims of some climate-change ‘skeptics’ that climate change came to a halt over the past decade, the reality is that both the drivers and the symptoms of climate change have been growing more rapidly since 1997 than before,” Holdren said.

Under business-as-usual emissions scenarios, Holdren said that “the least that can be expected” would be:

“…a worsening of the kinds of effects already being experienced – that is, further increases in floods, droughts, heat waves, and wildfires; changes in the frequency and intensity of weather extremes; continuing rise in sea level, most probably at an accelerating rate; increasing stress on water supplies in many regions already short of water; new and larger pest outbreaks afflicting crops and forests; still further stresses on agriculture and forestry arising from more frequent occurrence of ever higher temperature extremes; declines in coral reefs under the combined stress of higher water temperatures and continuing acidification of the surface layer of the ocean from absorption of part of the excess atmospheric CO2; expanded geographic range of tropical pathogens and their vectors; and further changes in the geographic distribution of many other species of plants, animals, and micro-organisms accompanied, in all likelihood, by an increase in the rate of extinctions.”

However, Holdren warned that the climate will not necessarily rise smoothly, especially as global temperatures rise beyond 2C above pre-industrial levels:

“Climate scientists worry about “tipping points” in the climate system, including ecosystems, meaning thresholds beyond which a small additional increase in average temperature or some associated climate variable results in major changes to the affected system. Examples of tipping points of potential concern include the complete disappearance of Arctic sea ice in summer, leading to drastic changes in ocean circulation and climate patterns across the whole Northern Hemisphere; drastic acceleration of the rate of ice loss from the Greenland and Antarctic ice sheets, driving rates of sea-level increase that could reach 6 feet per century or more; ocean acidification from CO2 absorption reaching a level that causes massive disruption in ocean food webs; and a flood of carbon dioxide and methane from warming tundra and thawing permafrost, accelerating the onset of all of the other impacts of concern.

“While our understanding of the global climate system and our ability to project its future behavior have grown enormously over the past couple of decades, we cannot yet predict with confidence exactly where on a rising temperature trajectory these or other thresholds would be crossed. It seems clear, however, that the probability of crossing one or more of them goes up sharply as the global-average surface temperature increase compared to 1900 goes above 3.6°F (2°C). That is a major reason for the growing global consensus that worldwide efforts should limit heat-trapping emissions sufficiently to hold the average temperature increase to 3.6°F (2°C) or less.” [emphasis added]

In concluding his written testimony, Holdren said:

“….the current state of knowledge about it (even though incomplete, as science always is) is sufficient to make clear that failure to act promptly to reduce global emissions to the atmosphere of carbon dioxide and other heat-trapping substances is overwhelmingly likely to lead to changes in climate too extreme and too damaging to be adequately addressed by any adaptation measures that can be foreseen..”

“It goes almost without saying that the United States, as the largest contributor to the cumulative additions of anthropogenic greenhouse gases to the atmosphere since the beginning of the Industrial Revolution and still today the second-largest emitter after China, and as the world’s largest economy and pre-eminent source of scientific and technological innovation, has both the obligation and the opportunity to lead the world in demonstrating that the needed emissions reductions can be achieved in ways that are affordable and consistent with continued economic growth, that create new jobs, and that bring further co-benefits in the form of reduced oil-import dependence and improved air quality.”

“President Obama is going to Copenhagen to underline that the United States is fully committed to assuming this leadership role. The Administration obviously will need the support of the Congress in delivering on this promise…”

Following Holdren was the hearing’s other witness, Dr. Jane Lubchenco, the Administrator of the National Oceanic and Atmospheric Administration (NOAA).  In her written testimony[PDF], Lubchenco also noted the impacts of climate change that already have been observed.

“At one time, we talked about what human-induced climate change might look like at some point in the future,” Lubchenco said.  “The latest science says that it’s happening now. We are now seeing the effects of human-induced climate changes on our landscape, our neighborhoods, schoolyards and farms, as well as our forests, beaches and mountains.”

Lubchenco warned of the far more serious impacts projected for coming decades and emphasized to the committee the importance not only of curbing emissions (what scientists call “mitigation”) but also of preparing for the impacts of climate change (often called “adaptation”).  Among the points Lubchenco made in her testimony:

•  “While climate change negotiations have primarily focused on mitigation of greenhouse gases, it is also critically important that we incorporate adaptation into our strategy. A bold strategy to reduce heat-trapping emissions is necessary to avoid the worst consequences of climate change, but even then some degree of future climate change will continue to occur despite mitigation efforts.”

•  “.. adaptation will be particularly challenging because the rate of change is escalating and is moving outside the range to which society has adapted in the past. The precise amounts and timing of these changes cannot be known with certainty. Because of this uncertainty and the high potential for surprises, adaptation plans will need to be robust, flexible, and able to evolve over time.”

•  “… meeting the challenge of preparing for and responding to climate change will require an unprecedented level of coordination among federal agencies, along with our nongovernmental and international partners.”

Lubchenco noted that some in the U.S. already are taking steps to prepare for climate change impacts:

“For example, Boston built one of its sewage treatment plants at higher ground to accommodate sea level projections over the next 50 years. Chicago is planting green roofs to cool its buildings and reduce the effects of urban heat waves. King County, Washington upgraded the specifications for a new regional wastewater treatment facility to include water reclamation capacity in response to the observed and projected declines in mountain snowpack. The State of California recently released a draft climate adaptation strategy that identified how state agencies can plan for climate impacts on multiple sectors, including public health, biodiversity and habitat, ocean and coastal resources, water management, agriculture, forestry, and transportation and energy infrastructure. Several other cities, counties, and states have developed comprehensive plans that address adaptation…”

During the hearing, the Republican members of the committee largely focused on the content of private emails among scientists that recently were stolen from a server at the Climate Research Unit at the University of East Anglia in the U.K.  The witnesses along with the Democrats on the committee responded.  We will address that element of the hearing in a separate blog posting.

For more on the hearing see the hearing Web page.  It includes video of the hearing and:

•  Opening statement of Chairman Edward J. Markey

•  Written testimony of Dr. John Holdren, Director, Office of Science and Technology Policy

•  Written testimony of Dr. Jane Lubchenco , Administrator, National Oceanic and Atmospheric Administration