How do we know the climate is changing?
The scientific community is certain that the Earth's climate is changing because of the trends that we see in the instrumented climate record and the changes that have been observed in physical and biological systems. The instrumental record of climate change is derived from thousands of temperature and precipitation recording stations around the world. We have very high confidence in these records as a whole. The evidence of a warming trend over the past century is unequivocal.
Many types of instrumental records point to a climate warming trend. Our streamflow records show an earlier peak in spring runoff; borehole temperature records in Alaskan permafrost as well as water temperature records on land and sea show the warming trend. The physical and biological changes that confirm climate warming include the rate of retreat in glaciers around the world, the intensification of rainfall events, changes in the timing of the leafing out of plants and the arrival of spring migrant birds, and the shifting of the range of some species.
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Using information from global climate models to inform policymaking—The role of the U.S. Geological Survey
This report provides an overview of model-based climate science in a risk management context. In addition, it summarizes how the U.S. Geological Survey (USGS) will continue to follow best scientific practices and when and how the results of this research will be delivered to the U.S. Department of the Interior (DOI) and other stakeholders to...
Terando, Adam; Reidmiller, David; Hostetler, Steven W.; Littell, Jeremy S.; Beard, T. Douglas; Weiskopf, Sarah R.; Belnap, Jayne; Plumlee, Geoffrey S.
A record of change - Science and elder observations on the Navajo Nation
A Record of Change - Science and Elder Observations on the Navajo Nation is a 25-minute documentary about combining observations from Navajo elders with conventional science to determine how tribal lands and culture are affected by climate change. On the Navajo Nation, there is a shortage of historical climate data, making it difficult to assess...
Hiza-Redsteer, Margaret M.; Wessells, Stephen M.
Ecosystem vulnerability to climate change in the southeastern United States
Two recent investigations of climate-change vulnerability for 19 terrestrial, aquatic, riparian, and coastal ecosystems of the southeastern United States have identified a number of important considerations, including potential for changes in hydrology, disturbance regimes, and interspecies interactions. Complementary approaches using geospatial...
Cartwright, Jennifer M.; Costanza, Jennifer
Desert wetlands—Archives of a wetter past
Scientists from the U.S. Geological Survey (USGS) are finding evidence of a much wetter past in the deserts of the American Southwest using a most unlikely source—wetlands. Wetlands form in arid environments where water tables approach or breach the ground surface. Often thought of as stagnant and unchanging, new evidence suggests that...
Pigati, Jeffery S.; Springer, Kathleen B.; Manker, Craig R.
Changing arctic ecosystems—What is causing the rapid increase of snow geese in northern Alaska?
Through the Changing Arctic Ecosystems (CAE) initiative, the U.S. Geological Survey (USGS) informs key resource management decisions for Arctic Alaska by providing scientific information on current and future ecosystem response to a warming climate. The Arctic Coastal Plain (ACP) of northern Alaska is a key study area within the USGS CAE...
Hupp, Jerry W.; Ward, David H.; Whalen, Mary E.; Pearce, John M.
USGS Arctic Science Strategy
The United States is one of eight Arctic nations responsible for the stewardship of a polar region undergoing dramatic environmental, social, and economic changes. Although warming and cooling cycles have occurred over millennia in the Arctic region, the current warming trend is unlike anything recorded previously and is affecting the region...
Shasby, Mark; Smith, Durelle
Climate change: evaluating your local and regional water resources
The BCM is a fine-scale hydrologic model that uses detailed maps of soils, geology, topography, and transient monthly or daily maps of potential evapotranspiration, air temperature, and precipitation to generate maps of recharge, runoff, snow pack, actual evapotranspiration, and climatic water deficit. With these comprehensive environmental inputs...
Flint, Lorraine E.; Flint, Alan L.; Thorne, James H.
Changing Arctic ecosystems: resilience of caribou to climatic shifts in the Arctic
The U.S. Geological Survey (USGS) Changing Arctic Ecosystems (CAE) initiative strives to inform key resource management decisions for Arctic Alaska by providing scientific information and forecasts for current and future ecosystem response to a warming climate. Over the past 5 years, a focal area for the USGS CAE initiative has been the North...
Gustine, David D.; Adams, Layne G.; Whalen, Mary E.; Pearce, John M.
Remote sensing of land surface phenology
Remote sensing of land-surface phenology is an important method for studying the patterns of plant and animal growth cycles. Phenological events are sensitive to climate variation; therefore phenology data provide important baseline information documenting trends in ecology and detecting the impacts of climate change on multiple scales. The USGS...
Meier, G.A.; Brown, Jesslyn F.
U.S. Geological Survey Climate and Land Use Change Science Strategy—A Framework for Understanding and Responding to Global Change
Executive SummaryThe U.S. Geological Survey (USGS), a nonregulatory Federal science agency with national scope and responsibilities, is uniquely positioned to serve the Nation’s needs in understanding and responding to global change, including changes in climate, water availability, sea level, land use and land cover, ecosystems, and global...
Burkett, Virginia R.; Kirtland, David A.; Taylor, Ione L.; Belnap, Jayne; Cronin, Thomas M.; Dettinger, Michael D.; Frazier, Eldrich L.; Haines, John W.; Loveland, Thomas R.; Milly, Paul C.D.; O'Malley, Robin; Thompson, Robert S.; Maule, Alec G.; McMahon, Gerard; Striegl, Robert G.
Changing Arctic ecosystems - measuring and forecasting the response of Alaska's terrestrial ecosystem to a warming climate
The Arctic Coastal Plain of northern Alaska is a complex landscape of lakes, streams, and wetlands scattered across low relief tundra that is underlain by permafrost. This region of the Arctic has experienced a warming trend over the past three decades, leading to thawing of on-shore permafrost and the disappearance of sea ice at an unprecedented...
Pearce, John M.; DeGange, Anthony R.; Flint, Paul L.; Fondell, Tom F.; Gustine, David D.; Holland-Bartels, Leslie E.; Hope, Andrew G.; Hupp, Jerry W.; Koch, Joshua C.; Schmutz, Joel A.; Talbot, Sandra L.; Ward, David H.; Whalen, Mary E.
Polar bear and walrus response to the rapid decline in Arctic sea ice
The Arctic is warming faster than other regions of the world due to positive climate feedbacks associated with loss of snow and ice. One highly visible consequence has been a rapid decline in Arctic sea ice over the past 3 decades - a decline projected to continue and result in ice-free summers likely as soon as 2030. The polar bear (Ursus...
Oakley, Karen L.; Whalen, Mary E.; Douglas, David C.; Udevitz, Mark S.; Atwood, Todd C.; Jay, C.
Walrus Sea-Ice Habitats Melting Away
Habitat for the Pacific walrus in the Chukchi Sea is disappearing from beneath them as the warming climate melts away Arctic sea ice in the spring, forcing the large mammals to “haul out” of the ocean and temporarily live on land.
Increased Sea Ice Drift Puts Polar Bears on Faster Moving Treadmill
A new study led by the U.S. Geological Survey and the University of Wyoming found that increased westward ice drift in the Beaufort and Chukchi seas requires polar bears to expend more energy walking eastward on a faster moving “treadmill” of sea ice.
A Mix of the Historic and Futuristic: Using Virtual Reality to Help Identify Tribal Climate Change Issues
Can indigenous knowledge of the local environment help inform climate science? If so, then what is the best way for climate scientists and tribal members to share what they know?
Changing Times, Changing Stories: Climate Change Perspectives Vary Notably Among Generations in Subarctic Alaska
New research from the U.S. Geological Survey and partners illustrates how climate change is perceived among different generations of indigenous residents in subarctic Alaska. While all subjects agreed climate change is occurring, the older participants observed more overall changes than the younger demographic.
Thousands of Walruses Forced to Haul Out in Alaska
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Polar Bear Outlook Favorable Under Certain Scenarios
“The scenarios predicted by our models are encouraging in that there are clear actions that humans can take to improve the chances that healthy polar bear populations persist in the future.” - Todd Atwood, USGS
A Warming Climate Could Alter the Ecology of the Deepest Lake in the United States
Warming air temperature is predicted to change water temperature and water column mixing in Oregon’s Crater Lake over the next several decades, potentially impacting the clarity and health of the iconic lake, according to a U.S. Geological Survey report released today.
How Climate Change Might Affect Polar Bears' Bodies
You really are what you eat. That’s the taking-off point for a new polar bear study, conducted by U.S. Geological Survey researchers with an assist from the Oregon Zoo — and published this week in the journal Physiological and Biochemical Zoology.
USGS Projects Large Loss of Alaska Permafrost by 2100
Using statistically modeled maps drawn from satellite data and other sources, U.S. Geological Survey scientists have projected that the near-surface permafrost that presently underlies 38 percent of boreal and arctic Alaska would be reduced by 16 to 24 percent by the end of the 21st century under widely accepted climate scenarios.
Arctic Mammals May Face Shrinking Habitat from Climate Warming
ANCHORAGE, Alaska — A new scientific study predicts that some of Alaska’s mammal species will respond to future climate warming by concentrating in northern areas such as the Arctic National Wildlife Refuge and the National Petroleum Reserve of Alaska. If true, for many species, this would be a significant northward shift into tundra habitats where they are currently absent.
Adaptive capacity of species - a fundamental component when assessing vulnerability to rapid climate change.
A new paper led by U.S. Geological Survey Ecologists Erik Beever (Northern Rocky Mountain Science Center) and Michelle Staudinger (Northeast Climate Science Center) addresses the importance of including adaptive capacity of species as a fundamental component when assessing vulnerability to rapid climate change.
As Climate Warms Hawaiian Forest Birds Lose More Ground to Mosquitoes
ISLAND OF HAWAI‘I, Hawaii — Hawai‘i, the name alone elicits images of rhythmic traditional dancing, breathtaking azure sea coasts and scenes of vibrant birds flitting through lush jungle canopy. Unfortunately, the future of many native Hawaiian birds looks grim as diseases carried by mosquitoes are due to expand into higher elevation safe zones.
A Record of Change: Science and Elder Observations on the Navajo N.
A Record of Change—Science and Elder Observations on the Navajo Nation is a 25-minute documentary about collaborative studies using conventional physical sciences, combined with tribal elder observations to show that local knowledge and conventional science partnerships can effectively document ecosystem change and determine the resulting challenges to livelihoods.
PubTalk 6/2017 — Effects of Climate Change: A Scientific Path Forward
Title: The Effects of Climate Change: A Scientific Pathway Forward
- The frequency of extreme and unpredictable weather events is increasing.
- What are the effects of an increase or decrease in carbon emissions?
- What is scientific research projecting for the future of climate change?
Polar Bear - POV Cams (Spring 2016)
This short clip is representative of a large amount of video footage of an adult female polar bear, equipped with a point of view camera, that is used by scientists to study polar bear behavior and feeding rates. Camera were attached to 10 animals in the southern Beaufort Sea over the course of several years, and stay on the animals for about 2 weeks until it is retrieved
Glacier Animation
The simulation below reflects the predicted exponential rise in atmospheric CO2 concentrations, a 2xCO2 "global warming" scenario, with a concurrent warming of 2-3 degrees centigrade (4-5 degrees Fahrenheit) by the year 2050. In addition it assumes that precipitation, primarily in the form of rain, will increase over the same time period about 10 percent (based on the
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1,500 walruses resting on shore
More than 1,500 walruses resting on shore at Cape Grieg in southeastern Bristol Bay.
Two Swimming Polar Bears
Data collected from long distance swims by Polar bears suggest that they do not stop to rest during their journey.
An Adult Polar Bear and Her Two Cubs
An adult female polar bear and her two cubs travel across the sea ice of the Arctic Ocean north of the Alaska coast.
2015 Climate Bootcamp
The Northwest Climate Science Center (NW CSC) is a Department of the Interior (DOI) initiative, sponsored by the USGS and jointly hosted by Oregon State University, the University of Idaho, and the University of Washington. One objective of the NW CSC is to support and train graduate students and early career professionals to work at the interface of scientific research on
What's the Big Idea? — Remote Sensing Understand Climate Change
Zhuoting Wu, research ecologist at the USGS Western Geographic Science Center, explains how the USGS uses remote sensing technology to help Tribal communities better understand the effects of climate change.
Climate Change Impacts on Aquatic Ecosystems in PNW
This webinar was held as a part of the Climate Change Science and Management Webinar Series, a partnership between the USGS National Climate Change and Wildlife Science Center and the FWS National Conservation Training Center. Webinar Description: Trout and salmon populations, which play a critical role in many ecosystems and economies, have dramatically declined in the
Extreme Climate Events and Species Population Dynamics
This webinar was held as a part of the Climate Change Science and Management Webinar Series, a partnership between the USGS National Climate Change and Wildlife Science Center and the FWS National Conservation Training Center. Webinar Description: Extreme events (floods, droughts, and fires) have a high public profile and changes in their frequency, magnitude, and duration
PubTalk 11/2012 — Understanding Climate-Wildlife Relationships
-- are American pikas harbingers of changing conditions?
by USGS Research Ecologist Erik Beever
- American pikas are denizens of rocky talus and lava-flow habitats in mountain ecosystems across western North America
- Mountain environments, cauldrons of climatic harshness, exhibit sharp topographic, vegetative, and