Part 1 of United States Climate Change Impact.
What is this Series?
this Series summarizes the science of climate change and the impacts of climate change on the United States, now and in the future. It is largely based on results of the U.S. Global Change Research Program (USGCRP), and integrates those results with related research [...]
Part 2 of United States Climate Change Impact.
Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing [...]
Part 3 of United States Climate Change Impact.
Key Messages:
Human activities have led to large increases in heat-trapping gases over the past century.
Global average temperature and sea level have increased, and precipitation patterns have changed.
The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human “fingerprints” also have [...]
Part 4 of United States Climate Change Impact.
Carbon dioxide concentration has increased due to the use of fossil fuels in electricity generation, transportation, and industrial and household uses. It is also produced as a by-product during the manufacturing of cement. Deforestation provides a source of carbon dioxide and reduces its uptake by trees and [...]
Part 5 of United States Climate Change Impact.
Carbon release and uptake
Once carbon dioxide is emitted to the atmosphere, some of it is absorbed by the oceans and taken up by vegetation, although this storage may be temporary. About 45 percent of the carbon dioxide emitted by human activities in the last 50 years is [...]
Part 6 of United States Climate Change Impact.
Precipitation patterns are changing
Precipitation is not distributed evenly over the globe. Its average distribution is governed primarily by atmospheric circulation patterns, the availability of moisture, and surface terrain effects. The first two of these factors are influenced by temperature. Thus, human-caused changes in temperature are expected to [...]
Part 7 of United States Climate Change Impact.
There is extensive statistical evidence from so-called “fingerprint” studies. Each factor that affects climate produces a unique pattern of climate response, much as each person has a unique fingerprint. Fingerprint studies exploit these unique signatures, and allow detailed comparisons of modeled and observed climate change patterns.
Scientists rely [...]
Part 8 of United States Climate Change Impact.
Some continued warming of the planet is projected over the next few decades due to past emissions. Choices made now will influence the amount of future warming. Lower levels of heat-trapping emissions will yield less future warming, while higher levels will result in more warming, and more [...]
Part 9 of United States Climate Change Impact.
Rising global temperature
All climate models project that human-caused emissions of heat-trapping gases will cause further warming in the future. Based on scenarios that do not assume explicit climate policies to reduce greenhouse gas emissions, global average temperature is projected to rise by 2 to 11.5°F by the [...]
Part 10 of United States Climate Change Impact.
Not all changes in the climate are gradual. There is the possibility of greater changes in climate than current scenarios and models project. The long record of climate found in ice cores, tree rings, and other natural records show that Earth’s climate patterns have undergone rapid [...]