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. Highlights describe the state of science at the time of publication of each yearly report, and may not reflect more recent advances in understanding. The date of publication of the source report is noted on each highlight page.

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]...

Model runs of CMIP5 models without greenhouse gas forcing (orange lines) demonstrate natural variability in average annual global surface temperatures expected without human influence on the climate.

Earth system models allow researchers to evaluate the size and strength of various influences on the climate system and identify the human contribution to the warming trend.

Earth system models allow researchers to distinguish “internal” climate variability (natural climate cycles) from the effects of “external” influences on the climate, both human and natural (including variations in incoming solar energy, volcanic eruptions, and greenhouse gas emissions from human activities). Model simulations of natural variability from the...

The January 2016 melt event on the West Antarctic ice sheet was captured by satellite and surface observations.

An observing campaign on the West Antarctic Ice Sheet is improving understanding of influences on recent ice loss and the implications for future sea level rise.

Antarctica holds the largest reservoir of ice on Earth and is significant contributor to sea level rise. The West Antarctic Ice Sheet, once considered relatively stable, has shed an increasing amount of ice...

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...

AmeriFlux FLUXNET2015 data collection sites overlaid on a map of global land cover types.

A global data collection network has built a strong foundation for carbon cycle understanding.

The AmeriFlux Network, which is supported by the Department of Energy, connects scientists from across the Western Hemisphere studying the exchange of carbon, water, and energy between ecosystems and the atmosphere. Since its launch in 1996, AmeriFlux has built a data record from 213 sites worldwide, called...

The Aedes aegypti mosquito is the primary vector for transmission of the Zika virus.

Interagency science investigated environmental influences on Zika transmission and helped support response efforts.

In February 2016, the World Health Organization declared the Zika outbreak spreading across the Americas since 2015 a Public Health Emergency of International Concern, based on Zika’s previously-unknown association with birth defects. The virus was first discovered in 1947 in Africa and had not previously been found in the Western Hemisphere. By February 2016, the outbreak had spread to 48 countries and territories in the Americas...

Mangrove forests store large amounts of carbon, protect the coastline from erosion, and provide shelter for many species.

A new research network aims to accelerate discoveries in the science of these important natural carbon sources and sinks.

Coastal wetlands provide protection from wind and waves, support habitats and fisheries, and store large amounts of atmospheric carbon dioxide for centuries to millennia. These ecosystems can also be sources of greenhouse gas emissions to the atmosphere; wetlands that do not have the capacity to keep pace with sea-level rise, for example, can erode and release soil carbon rapidly to the atmosphere. Freshwater and brackish wetlands also emit methane, a...

Researchers are improving understanding of how shifts in climate conditions affect agricultural production, as well as the value of providing advance climate information to producers.

Climate variability and change affect agricultural yields and livelihoods^[1]. Improving our understanding of how the interaction of climate variability and change affects agricultural production, particularly on regional scales that are more relevant to decision making, is an important research frontier. As part of the joint NSF-USDA...

Collaboration across the modeling community supports critical experiments and scientific advancement.

U.S. climate modeling centers play a central role in understanding and predicting global change on seasonal to centennial timescales. They are engaged in the Coupled Model Intercomparison Project (CMIP), which produces climate projections underpinning the assessments conducted by the Intergovernmental Panel on Climate Change and the U.S. National Climate Assessment. Models developed by these centers are designed for different purposes, from providing operational forecast...

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Highlights

Scientists investigate the effects of carbon emissions from thawing permafrost soils

Exploring human and natural influences on climate

Investigating ice sheet change in Antarctica

Detecting the drivers of forest change in Alaska and the Arctic

Understanding carbon cycling in Arctic ecosystems

Supporting twenty years of carbon cycle understanding

Responding to the Zika outbreak

Understanding carbon flows in vulnerable coastal wetlands

Modeling the impacts of climate variability on agriculture

Enhancing coordination among U.S. modeling centers