Walruses in the Chukchi Sea during a tagging survey onboard the Norseman II in June 2010.

A just-released USGS film will take you on a journey along with USGS researchers tracking walruses going about their daily lives in the remote Chukchi Sea. The film, Tracking Pacific Walrus: Expedition to the Shrinking Chukchi Sea Ice, follows scientists as they travel to the Chukchi Sea to examine how these mammals are faring in an Arctic environment with sparse summer sea ice and increased human activity.

The USGS-produced film contains exclusive footage of the large mammals in their natural habitat, documenting the lives of these huge animals as they raise their young, dive for clams and worms on the ocean floor or congregate with other walruses.

A Changing Arctic Climate Means Changing Arctic Ecosystems

Arctic sea ice is melting faster than forecasted by many of the top climate models: the first ice- free summer is now predicted to occur by 2035, perhaps as soon as 2025.

But warming temperatures are causing other changes as well — increased coastal erosion, deteriorating permafrost, and major changes in the dynamics of freshwater flows. These changes influence biological communities and the ways in which human communities interact with them. For example, the longer open water season in the Arctic is allowing increased shipping, tourism, energy production and other human activities in this remote region.

As part of the USGS Changing Arctic Ecosystems initiative, USGS researchers are identifying and investigating the linkages among physical processes (such as sea ice melting at a faster rate), ecosystems and wildlife populations.  By understanding the degree to and manner in which wildlife species adapt to rapid environmental change, resource managers and policy makers will have a better foundation for making critical decisions now and in the future.

New Research on Pacific Walrus and Sea Ice

The information gained through tracking large marine mammals, such as polar bears and walruses, is helping USGS scientists understand how disappearing Arctic sea ice is affecting the region’s ecosystems and the species that inhabit these ecosystems.

Scientists prepare to radio-tag walruses in the Chukchi sea to track movements as sea ice is reduced in the region.

For example, recently published research by USGS and Russian scientists revealed that diminishing summer sea ice in the Arctic over the past 5 years has caused behavioral changes in Pacific walruses. The population-level effects of these changes are unknown and the subject of active investigation by USGS.

Using a simple darting system, scientists attached radio-tracking tags to 251 walruses in the Chukchi Sea. The tags transmitted the animals’ whereabouts and whether they were in the water and feeding. Using the tagging data gathered from 2008-2011, scientists created detailed maps of the walruses’ seasonal movements and feeding patterns relative to the location and amount of sea ice.

When Chukchi Sea Ice Retreats North of the Continental Shelf Edge, Walruses Haul Out

The study found that due to earlier melting of the ice in the summer, walruses arrived earlier in their northern feeding grounds on the broad continental shelf of the Chukchi Sea. When the sea ice over the continental shelf melted completely in the fall, however, they “hauled out” onshore in large aggregations and foraged for food closer to shore. [Hauling out refers to the behavior associated with seals and walruses of temporarily leaving the water for sites on land or ice.]

The specific effects of these behavioral changes are not yet understood; however, scientists do know that while onshore, young walruses are susceptible to mortality from trampling. USGS has recently published a study that examined the population effects of this type of mortality, finding that loss of young animals to haul-out mortality has a greater effect on the population than loss of adult females in the harvest.  In light of this finding, the U.S. Fish and Wildlife Service is increasing its ongoing efforts to protect hauled-out walruses from disturbance.

Additionally, hauling out onshore and using nearshore feeding areas may require more energy for animals used to simply diving off their sea-ice platforms for food at the bottom of the shallow Chukchi Sea.

Data from this study will provide resource managers with basic information on areas important for walruses, such as the Hanna Shoal region, as human activities in the Arctic increase. The areas of walrus foraging observed in this study overlap with oil and gas lease blocks leased by BOEM (Bureau of Ocean Energy Management).

Adult female walrus on ice floe.

The study, published as this month’s feature article in the journal Marine Ecology Progress Series, is part of the USGS Changing Arctic Ecosystems initiative at the Alaska Science Center.

Young boys working in a newly cropped field in Africa.

In parts of eastern Africa, drought is of increasing concern, as poor families suffer from food shortages and the inability to grow crops and sustain livestock. Stunted growth in children due to malnutrition has also been linked to climate trends in Africa.

Drought conditions are expected to continue as global temperatures continue to rise and rainfall declines across parts of eastern Africa.

This poses increased risk to millions of people in Africa who currently face potential food shortages.

What’s being done to help?

The USGS is involved in a variety of research efforts to help understand current and future conditions in Africa, helping to inform plans to provide aid.

The Famine Early Warning Systems Network, or FEWS NET, is one endeavor that has already made great strides in helping to address this issue. FEWS NET helps target more than $1.5 billion of assistance to more than 40 countries each year.

FEWS NET examines the populations of the developing world with the most food insecurity, identifying critical situations in which food aid will be needed. These are populations whose livelihoods are typically tied to subsistence rain-fed agriculture and pastoralism.

FEWS NET is sponsored by the U.S. Agency for International Development (USAID) Office of Food for Peace and the USGS is actively involved.

FEWS NET at the United Nations Climate Convention

A USGS presentation on FEWS NET will be a featured side event on November 30, 2011, at the United Nations 17^th annual Conference of the Parties (COP-17) in Durban, South Africa. The convention’s purpose is to develop international agreements and a declaration of policies and practices for combating climate change and its impacts around the world.

A herder moves cattle through a barren landscape in eastern Africa.

Climate forecasts and remote sensing help spot future trouble

FEWS NET has developed its own climate services to provide decision makers with early identification of agricultural drought that might trigger food insecurity. Scientists use climate forecasts to develop forward-looking food security assessments that are based on expected agricultural outcomes for the season ahead.

Since networks of ground observation stations are often sparse or reported late in FEWS NET countries, satellite remote sensing of vegetation and rainfall fills in the gaps. Remote sensing from space allows for rapid, accurate assessments of a broad range of environmental and agricultural conditions. USGS scientists provide the technologies and expertise to support remote sensing for FEWS NET activities.

Early warning of famine in Somalia helps pre-position food supplies

On July 20, 2011, the United Nations declared parts of Somalia as a region of famine. The decision was supported by FEWS NET and USGS observational evidence of conditions in the area.

The declaration was the culmination of early warning communications encouraging — months before the crisis — that government and other agencies pre-position food and supplies in the region.

“None of the many uses of Earth-observing satellites is more vital — or has as much potential for prompting timely humanitarian intervention — as famine early warning,” said USGS Director Marcia McNutt. “Remote sensing from space allows USGS scientists to provide rapid, accurate assessments of a broad range of environmental and agricultural conditions.”

The eastern Horn of Africa, the continental region that encompasses Somalia, has experienced two consecutive seasons of very poor rainfall resulting in the worst drought in 60 years. Crops have failed, livestock deaths are widespread, and food prices are very high. While the rains this winter have been good, food prices remain high, and the food security situation remains insecure.

Stunted growth linked to malnutrition and climate change

Other USGS research is helping to identify the impacts of a changing climate on Africa’s people. Scientists recently discovered that malnutrition and dry hot living conditions are linked to stunted growth in Mali, West Africa.

USGS research found that Mali was becoming substantially warmer and a little bit drier. Scientists also knew that farmers and those who make a living raising sheep, cattle, goats, or camels were poor, and that stunted growth was occurring throughout Mali.

Scientists wondered if there could be a link between human health and increasingly warm and dry conditions.

To investigate, the USGS worked with the University of California, Santa Barbara, to study climate observations and demographic and health data. The Demographic and Health Survey program routinely compiles data from surveys in 90 countries to study trends in health and population. Scientists analyzed statistics on specific villages in Mali and found that there was a link between a warmer climate and increased stunting.

Population growth combined with the impacts of warming will further increase these health impacts.

Stunting was also linked to other factors, such as mother’s education and the water supply system. Women’s education, improved water supplies, and agricultural development could help to address malnutrition and stunting in Mali.

An article on this research was published in in the journal, Applied Geography, by San Diego State University, the University of California, Santa Barbara, and the USGS.

A Food Security Assessment in Somalia found severe impacts on livestock due to drought conditions.

Other studies underway

Other new research includes the discovery that the warming of the Indian and western Pacific oceans (which is linked to global warming) affects rainfall over large areas of the Horn of Africa. As the globe has warmed over the last century, the Indian Ocean and western Pacific have warmed especially fast.

The resulting warmer air and increased humidity over the Indian and western Pacific oceans produce more frequent rainfall in that region. The air loses its moisture during rainfall, and then flows westward and descends over Africa, leading to decreased rain in parts of eastern Africa. Trends toward increased frequency of drought that we are seeing now are likely to continue into the future as warming continues.

A few recent articles on this research were published in the journal, Climate Dynamics, by scientists with the USGS, the University of California, Santa Barbara, and Los Alamos National Laboratory. The most recent article concludes that global warming will lead to a decrease in rainfall during the summer monsoon season, from June to September, across southern Sudan, southern Ethiopia, and northern Uganda.  Another article concluded that eastern Africa, particularly Kenya and southern Ethiopia, will also have a significant decrease in rainfall during the long-rains season from March to June.

USGS scientists are working hard to translate these technical studies into reports for decision makers. To date, they have completed summary fact sheets focused on Sudan and Kenya.

Scientists also found that some regions, like northern Ethiopia, are not getting drier due to current warming temperatures. Rainfall varies dramatically across all of eastern Africa, with high mountainous areas typically receiving many times the rainfall received in low-lying areas. Therefore, agricultural growth in these climatically safe regions could help offset rainfall declines in other locations.

Start with science

Scientists are looking at clues and changes in nature to understand the impacts of global warming. In Africa, impacts are seen across the landscape — on farms and even in humans.

By starting with science, well-informed decisions can be made to help Africa as it faces drought, famine, and health concerns.

FEWS NET partners include the USAID, Chemonics International, the USGS, NASA, NOAA, and the USDA. The Geography Department at the University of California, Santa Barbara, is a partner to the USGS in this effort.

Want more information?

Listen to a podcast interview with USGS scientists as they discuss ongoing efforts to understand conditions in Africa.