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Gregory Asner, PhD
Environmental Scientist<

Greg Asner is an Earth scientist who studies the effects of humans on ecosystems and our climate. He got his start in Earth science in the early 1990s while living in Hawai'i and working for The Nature Conservancy. During this time, Greg realized that human activities on an isolated archipelago in the middle of the Pacific Ocean might be an important analog for similar changes throughout the world. Human-caused changes on an island in a vast ocean could be a prelude to changes on our planet within our vast solar system. Since his start in Hawai'i, Greg built a research program to study the impacts of humans on ecosystems worldwide.

Dr. Asner's scientific training spans the fields of engineering, radiation physics, ecology, biogeochemistry and remote sensing. He started his laboratory at the University of Colorado and then moved his program to the Carnegie Institution's Department of Global Ecology in 2001. Greg and company combine field studies, airborne and satellite sensors and computer modeling in unique ways to study ecosystems at the regional scale. His efforts center on the use of new, cutting-edge technologies for studies of ecosystem structure and chemistry. Most of these technologies are based from aircraft, but a few of these capabilities are now on satellites orbiting the Earth.

Greg has applied his work to environmental problems in tropical forests and arid ecosystems of the world. From the American Southwest to the Brazilian Amazon, he has developed new ways to detect land degradation resulting from human activities and climate change. In places like the Southwestern US and Argentina, he uses instruments on aircraft – from helicopters to high-flying surveillance planes – to measure the structure and chemistry of arid ecosystems as they change to deserts, a process known as desertification. In the Amazon Basin, Asner and his colleagues have combined extensive field studies and satellite technologies to quantify for the first time the extent and ecological impacts of timber harvests on the tropical forest.

Despite the worldwide extent of Asner's studies, Hawai'i is still a central focus of his research. He and his colleagues benefit from the diversity of ecosystems found in Hawai'i, which range from tropical forest to deserts. They use this incredible localized ecological variation to develop the next generation of aircraft and satellite-based approaches for global studies of ecosystems. While doing so, Asner is returning the favor by turning his capabilities towards one of Hawai'i's greatest ecological problems – invasive species. From field studies to aircraft and space-based remote sensing, Greg tracks the location and ecological impacts of invading species that have come to the islands by ways of human activities and population growth. He thinks that lessons learned in Hawai'i will make a difference in understanding our home planet.

Relevant Publications

Defries, R., Foley, J. and Asner, G.P. (2004). Trade-offs from land-use change: Using ecological knowledge to balance human needs and ecosystem function. Frontiers in Ecology and Environment, 2(5), 249-257.

Defries, R., Asner, G.P. and Houghton, R.A. (2004). Ecosystems and land use change. Washington, DC: American Geophysical Union. 344 pp.

Additional Asner Research

NASA Airborne Observatory Reveals Land Changing to Desert Off-site Link

Earth Observatory at NASA.gov Off-site Link

Amazon drought now measured from space Off-site Link

ScienCentral News: Food for Thought Off-site Link

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