Research Projects: Global Warming and the Human-Nature dimension in Siberia: Social Adaptation to the Changes of the Terrestrial Ecosystem, with an Emphasis on Water Environments

Global Warming and the Human-Nature Dimension in Siberia:
Social Adaptation to the Changes of the Terrestrial Ecosystem, with an Emphasis on Water Environments

Inoue Gen RIHN

yamaguchi Yasushi Nagoya University

sasai Takahiro Nagoya University

ohta Takeshi Nagoya University

hiyama Tetsuya RIHN

takakura Hiroki Tohoku University

okumura Makoto Tohoku University

Global warming will likely transform Siberian environments. Early evidence indicates that the hydrological, carbon, and methane cycles are undergoing rapid change, with potentially grave impact on Siberian flora and fauna. Human inhabitants, who have adapted to great changes in social structure and environment in the past, will be forced to adapt again, but to a cascading series of environmental changes whose dimensions are understood only in outline. This project uses multiple satellite and surface systems to track changes in the carbon and hydrologic cycles and the cryosphere, and assesses their likely interactions and significance for human inhabitants of the region. The project is jointly conducted by Japanese and Russian universities and research institutes.

Climate models predict that evidence of climate change will appear early in Siberia and, as it is located in the high latitudes and in a continent whose climate is etermined by radiative cooling, that its effects will be more significant than in other places. In fact, there is already clear evidence of declining ice-content, forest degradation associated with wet environments, and increasing flood frequency and intensity.

Rising temperatures can trigger drastic change in ice, snow and permafrost environments, increase the incidence and intensity of extreme weather events, including flood and forest fires, and alter the structure of interactions between principal biophysical elements. The immediate effect of these changes is likely to increase the concentrations of carbon dioxide, methane and water vapor in the atmosphere, all of which contribute to further warming (Fig. 2) Warmer environments also present new opportunities for large-scale resource extraction, which in turn increases the risk of environment damage, including natural gas leakage from gas pipelines.

Research takes place in the Lena Basin in East Siberia, an area characterized by a fragile symbiotic relationship between permafrost and forest. Permafrost provides moisture to the forest by preventing soil water from draining into deeper soil, while the forest shadows the permafrost from sunlight. A significant change in this relationship could release into the atmosphere an enormous amount of carbon that is currently stored in trees and soil. Our research in the area is conducted by three interrelated groups.

This group combines “bottom-up” and “top-down” observation of the Siberian carbon cycle. Surface spectral ASTER or MODIS data are combined with a terrestrial carbon-energy-water budget model (BEAMS) developed by our group to examine changes in land cover. This data will be supplemented by monitoring of greenhouse gases in Siberia enabled by Japan's launch of the GOSAT (Greenhouse gases Observing SATellite) in January 2009. GOSAT data should rectify the scarcity of ground-based monitors of greenhouse gases in Siberia. This data will improve our understanding of the CO2 and CH4 budget in Siberia and track greenhouse gas emissions due to forest fires and malfunctioning natural gas pipelines. Spectral surface data also allows measurement of flood extent and frequency, area of forest degradation or loss, and change in reindeer habitat, phenomena which are also of relevance to the human ecology group.

Ice cover in the Arctic Sea is decreasing more rapidly than predicted; atmospheric water vapor will be supplied year round and precipitation will increase in Siberia. How will Siberian forests respond to a wetter environment? There is evidence of sudden forest die-off (Photo 2), perhaps due to soil moisture surpassing a critical threshold. Isotope analysis of tree rings provides insight into the past conditions of forest-tundra growth. We have constructed a new monitoring tower at Us'tmaya, located about 500km to the south of the existing monitoring tower at Yakutsk, to measure water vapor, carbon dioxide and heat budget. Precipitation at the new site is 1.5 times greater than at Yakutsk.

Siberia's human inhabitants have adapted to the cold environment, but current environmental changes affect their life patterns in unprecedented ways. Field studies have revealed that availability of drinking water (stored as ice in winter), availability of bio-fuels (mainly wood), pasture land productivity, and patterns of animal reproduction and hunting are now changing. The number of wild and domestic reindeer has dramatically declined in recent years. Climate warming has led to wetter environments which negatively affect reindeer range and breeding and grazing grounds. There may also be some linkage between decreasing reindeer populations and recent economic conditions. We are going to investigate these changes by interviewing famers and hunters in villages, and by mounting tracking devices on wild reindeer.

Climate change and social change intersect in complex ways and are often difficult to predict. We believe that the human dimension of climate change in Siberia is a very important factor, as human reaction to changing environments has the potential to exacerbate, or perhaps mitigate, negative impacts. We begin by analyzing different actors' perceptions of contemporary change, emphasizing perception of abnormal conditions and of what constitutes a “natural disaster”. Analysis of difference in social response to environmental change will improve understanding of social-ecological fragility and vulnerability.