Draft Report Warns Temperatures Could Increase by up to 10 Degrees

On January 11, the National Climate Assessment Development Advisory Committee of the U.S. Global Change Research Program released the draft National Climate Assessment (NCA) for public comment. More than 240 scientists from the public and private sectors worked on the 400-page report, which will be finalized in 2014. The report was prepared by a working group of 13 federal agencies in compliance with the Global Change Research Act of 1990 (P.L. 101-606) to help the nation understand and respond to climate change. The last NCA was released in 2009.

The report offers an overall climate change assessment for the U.S. and also breaks down the effects of climate change for localities across the country, dividing the nation into eight regions.

The report concludes, “Climate change is already affecting the American people. Certain types of weather events have become more frequent and/or intense, including heat waves, heavy downpours, and, in some regions, floods and droughts. Sea level is rising, oceans are becoming more acidic, and glaciers and arctic sea ice are melting. These changes are part of the pattern of global climate change, which is primarily driven by human activity.”

Some major findings of the report include:

  • "[The] global climate is changing, and this is apparent across the U.S. in a wide range of observations. The climate change of the past 50 years is due primarily to human activities, predominantly the burning of fossil fuels."
  • "Some extreme weather and climate events have increased in recent decades, and there is new and stronger evidence that many of these increases are related to human activities."
  • "Infrastructure across the U.S. is being adversely affected by phenomena associated with climate change, including sea level rise, storm surge, heavy downpours, and extreme heat."
  • "Adverse impacts to crops and livestock over the next 100 years are expected. Over the next 25 years or so, the agriculture sector is projected to be relatively resilient, even though there will be increasing disruptions from extreme heat, drought, and heavy downpours. U.S. food security and farm incomes will also depend on how agricultural systems adapt to climate changes in other regions of the world."
  • "Human-induced climate change is projected to continue and accelerate significantly if emissions of heat-trapping gases continue to increase."
  • "Planning for adaptation (to address and prepare for impacts) and mitigation (to reduce emissions) is increasing, but progress with implementation is limited."

Source: Draft National Climate AssessmentThe two maps show the projected change in average surface air temperatures in the later part of this century (2070-2099)
relative to the later part of the last century (1971-1999) under a scenario that assumes substantial reductions in
heat trapping gases (B1, left) and a higher emissions scenario that assumes continued increases in global emissions (A2, right).

(Source: Draft National Climate Assessment)

According to the authors, temperature increases of two to four degrees Fahrenheit are likely in most areas around the country, and if greenhouse gas emissions are not reduced, the temperature increases could be as high as five to 10 degrees Fahrenheit by the end of the century. The environmental and human health impacts of climate change are already being felt around the country, but the effects in Alaska are most pronounced. The report states, “The most dramatic evidence is in Alaska, where average temperatures have increased more than twice as fast as the rest of the country. . .Of all the climate-related changes in the US, the rapid decline of Arctic sea ice cover in the last decade may be the most striking of all.”

According to a statement released by Dr. John P. Holdren, director of the White House Office of Science and Technology Policy, and Dr. Jane Lubchenco, administrator of the National Oceanic and Atmospheric Administration, the NCA is intended “to be used widely by public and private stakeholders who need information about climate change in order to thrive – from farmers deciding which crops to grow, to city planners deciding the diameter of new storm sewers they are replacing, to electric utilities and regulators pondering how to protect the power grid.“ They cautioned that, “The draft NCA is a scientific document – not a policy document – and does not make recommendations regarding actions that might be taken in response to climate change.”

Nonetheless, climate change has been identified by President Barack Obama as a priority for his second term. In an interview with Time magazine after being named “the Person of the Year,” the president said that his top priorities included the economy, immigration reform and climate change and energy. Without providing any specifics the President expressed the importance of the issue, especially to younger generations: “On an issue like climate change, for example, I think for this country and the world to ask some very tough questions about what are we leaving behind, that weighs on you. And not to mention the fact I think that generation is much more environmentally aware than previous generations.”

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