Highlights

Since 1989, the U.S. Global Change Research Program (USGCRP) has submitted annual reports to Congress called Our Changing Planet. The reports describe the status of USGCRP research activities, provide progress updates, and document recent accomplishments.

In particular, Our Changing Planet highlights progress and accomplishments in interagency activities. These highlights represent the broad spectrum of USGCRP activities that extend from Earth system observations, modeling, and fundamental research through synthesis and assessment, decision support, education, and public engagement.

Methane emitted from thawing permafrost below an Arctic thermokarst lake is trapped in bubbles of many different sizes and shapes as the ice grows during the winter.

Long-frozen northern soils known as permafrost contain one of the world’s largest stores of organic carbon. This reservoir is stable while soils are frozen, but as permafrost thaws, decomposition of biomass by microbes produces the heat-trapping gases carbon dioxide and methane, returning soil carbon to the atmosphere where it contributes to climate change. Permafrost carbon stores are expected to be increasingly vulnerable to decomposition as the climate continues to change, leading to a feedback cycle of further warming and permafrost thaw.^[1]...

Regional comparisons of submarine (1958–1976 and 1993–1997), ICESat (2003–2007), and CryoSat-2 (2011–2016) ice thickness data, showing declines in ice thickness over time.

Satellite observations of sea ice thickness provide an opportunity to improve seasonal predictions of Arctic sea ice cover.

Arctic sea ice grows and melts each year with the seasons, reaching its low point in September. Summer sea ice cover has shrunk significantly over the past thirty years, although variation from year to year means that the downward trend is not uniform. Arctic sea ice plays a critical role in regulating weather and climate in and beyond the region. Sea ice decline activates a feedback loop in the climate system: as highly...

G-LiHT measurements for an area within Bonanza Creek Experimental Forest near Fairbanks, Alaska.

Scientists are using aerial and ground survey methods to measure change in Alaska’s interior forests and its impact on ecosystem services.

The boreal forests of interior Alaska are changing rapidly as the climate warms. Wildfires are more frequent and more severe, and declines in growth of spruce trees may be driving a shift towards ecosystems normally found in warmer climates. These changes can have significant impacts on the quality of wildlife habitat and ecosystem services that support the subsistence economies of many native Alaskan...

Using 29 years of data from Landsat satellites, researchers at NASA found extensive greening in the vegetation across Alaska and Canada.

Scientists are using satellites to collect detailed data on forest change in remote parts of Alaska and the Arctic.

Rapid warming in the Arctic and boreal regions of Alaska is affecting boreal forests and tundra ecosystems in a number of ways. Higher temperatures and changes in precipitation have led to a higher incidence of wildfire and increased tree mortality from drought, insects, and disease. Increases in the length of the growing season and the amount of energy produced by vegetation have also been observed. While tracking how climate...

Map shows the average active layer thickness (ALT) at the end of the growing season for the Barrow, Alaska region that contains the NGEE Arctic study site.

Scientists are gaining new understanding of processes that control greenhouse gas emissions from Arctic permafrost, a potential driver of significant future warming.

Rapid warming in the Arctic is causing carbon-rich soils known as permafrost, previously frozen for millennia, to thaw. As thawing soils decompose, the greenhouse gases carbon dioxide and methane are released into the atmosphere in varying proportions depending on the conditions under which decomposition occurs. Permafrost emissions could contribute significantly to future warming...

A lake near Fairbanks, Alaska shows signs of thawing permafrost below the surface

By monitoring trends such as permafrost thaw, shifts in wildfire, and changing wildlife habitats, a multi-year field campaign seeks to provide the scientific basis for informed decision-making in response to change.

Climate change in the Arctic and Boreal Region is unfolding faster than anywhere else on Earth. Observations reveal reduced Arctic sea ice, widespread changes to coastlines and waterways, thawing of permafrost soils and decomposition of long-frozen organic matter, and shifts in ecosystem structure and function. These changes have far-reaching impacts in the...

The figure shows long-term averages of Arctic summer sea ice concentration simulated by an adaptation of CICE/Icepack

Interagency collaboration supports predictions of Arctic sea cover used by the U.S. Navy and other operational and research organizations.

Summer sea ice cover in the Arctic Ocean shrunk significantly since the early 1980s, with particularly rapid declines in recent years^[1]. Arctic sea ice plays a key role in regulating weather and climate in and beyond the region^[2], and projections of how sea ice cover will change in the coming years are critical for...

Modeling Permafrost Response to Climate Change

Vast quantities of carbon—twice the size of the current amount in the atmosphere—are stored in frozen permafrost soils in Arctic regions. The Arctic climate is warming much more rapidly than the global average, leaving these carbon pools highly vulnerable to release into the atmosphere as carbon dioxide and methane as soils thaw and decompose, leading to a feedback cycle of further warming and increasing carbon release. The potential for these carbon stocks to increase global-warming rates, and the rapid changes already observed in the permafrost region, have captured the attention of...

Improving Predictions of Changing Arctic Ecosystems

A key challenge for Earth System Models is accurately representing land surface and subsurface processes and their complex interactions in a warming climate. This is true for ecosystems across the globe, but particularly critical for Arctic ecosystems, which are projected to warm at a rate twice that of the global average by the end of the 21st century. The Next-Generation Ecosystem Experiments in the Arctic (NGEE-Arctic) project is addressing this challenge by integrating process studies, ecosystem observations, and computational...

Tracking Methane Emissions from Arctic Tundra

The Arctic tundra is a cold, desert-like biome, with a layer of permanently frozen soil and organic matter below the surface containing vast stocks of carbon. As Arctic tundra soils warm in response to climate change, methane emissions from decomposing organic material could increase dramatically, representing a potentially significant positive feedback on climate warming. However, seasonal and climatic influences on methane emissions from these systems are not well understood outside of the summer months, representing a major uncertainty for the Arctic methane budget. To help address a...

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Highlights

Scientists investigate the effects of carbon emissions from thawing permafrost soils

Advancing seasonal predictions of Arctic sea ice

Monitoring change in Alaskan forests

Detecting the drivers of forest change in Alaska and the Arctic

Understanding carbon cycling in Arctic ecosystems

Monitoring change in Alaska and the Arctic

Predicting Arctic sea ice change

Modeling Permafrost Response to Climate Change

Improving Predictions of Changing Arctic Ecosystems

Tracking Methane Emissions from Arctic Tundra