Today, the White House released a detailed assessment of climate change's domestic impacts. And the conclusions will sound familiar to anyone who's followed recent reports from a United Nations-convened panel of scientists: climate change is here, it's already having widespread impacts, and governments need to start preparing.
"Americans are noticing changes all around them," says an opening paragraph in the National Climate Assessment's
overview. "Summers are longer and hotter, and extended periods of unusual heat last longer than any living American has ever experienced. Winters are generally shorter and warmer. Rain comes in heavier downpours. People are seeing changes in the length and severity of seasonal allergies, the plant varieties that thrive in their gardens, and the kinds of birds they see in any particular month in their neighborhoods."
The report includes projected impacts as well as some of the changes that scientists and researchers are already observing. And it breaks them down by region. In the Northeast, for example, the amount of precipitation falling during heavy events — downpours and heavy snowfall, in other words — increased by 71 percent between 1958 and 2012, the report says. And average temperatures in the region increased by 2 degrees Fahrenheit from 1895 to 2011, the report says. (Information on the Northeast is available here
The assessment predicts continued warming, more intense heatwaves, flooding, and increased coastal vulnerability to hurricane damage due to sea level rise.
The report is massive, and much of what it says should come as no surprise. Like past climate reports, it presents a lot of information on climate trends and their implications. And it calls for cuts in carbon emissions.
But the assessment emphasizes planning for and adapting to the impacts of climate change, including observed trends and predicted problems.
"Either way you cut it, the horse is already out of the barn, so to say," said David Wolfe, a Cornell University professor and one of the lead authors on the Northeast section, during a conference call with reporters this morning.
Agriculture in the Northeast may provide a prime example. The assessment says that changing temperature and precipitation patterns are factors in crop damages. And the losses, the report says, often amount to millions of dollars. It also clearly states the challenges of addressing the problems. From the report:
"Research and outreach efforts are underway in the region to help farmers find ways to cope with a rapidly changing climate, take advantage of a longer growing season, and reduce greenhouse gas emissions, but unequal access to capital and information for strategic adaptation and mitigation remains a challenge. Financial barriers can constrain farmer adaptation. Even relatively straightforward adaptations such as changing varieties are not always a low-cost option. Seed for new stress-tolerant varieties is sometimes expensive or regionally unavailable, and new varieties often require investments in new planting equipment or require adjustment in a wide range of farming practices. Investment in irrigation and drainage systems are relatively expensive options, and a challenge for farmers will be determining when the frequency of yield losses due to summer water deficits or flooding has or will become frequent enough to warrant such capital investments."
During the conference call, Wolfe said that the farmers he's met are concerned about the risks posed by extreme weather. He's been helping to develop web-based tools, which incorporate climate projections, that farmers can use to determine when it'd make sense to make certain investments.
Wolfe said local governments and homeowners should also be able to use the assessment to guide investments, too.