Interactions Between Biomass Burning and Climate: Conclusions Drawn from the Workshop

Abstract

An international workshop with the title: “Biomass burning and its inter-relationships with the climate system” was held in Wengen, Switzerland, from 28 September to 2 October 1998. The workshop was attended by some 50 scientists from 12 countries. It was co-sponsored by the University of Fribourg, ENAMORS (the European Network for the development of Advanced Models to interpret Optical Remote Sensing data), the Swiss National Science Foundation and the Swiss Federal Institute for Forest, Snow and Landscape Research.

A wealth of new material was presented on the inter-relationships between climate and biomass burning. Forest fires were the subject of particular attention as a result of their world-wide prominence during the past 12 months. The period 1997–98 was characterised by a strong El Nino event, resulting in much drier conditions than normal in areas such as Indonesia and Brazil. This, in turn, resulted in many of the small-scale fires lit to clear land for agricultural activities getting out of control and spreading to primary forest areas. Devastating forest fires also occurred elsewhere, and large areas of forest were burned in 1997–98 in areas as disparate as Canada, Russia, Mexico and Greece. While there has been enormous progress in our understanding of how biomass burning affects climate, there are still many shortcomings. Even with the available technology and resources, it is still difficult to assess exactly the area of the Earth’s surface burned in the last 12 months and how much of carbon dioxide and other radiatively-active greenhouse gases were released into the atmosphere. There is little doubt in the scientific community that satellite-based remote sensing systems provides the key to the global monitoring of biomass burning. A significant amount of research has been directed towards developing new algorithms for fire detection and monitoring, which in turn, has improved estimates of the global extent of biomass burning considerably. It is expected that these capabilities will continue to improve as new satellite systems are deployed over the next several years, especially new geostationary meteorological satellites and polar-orbiting platforms such as EOS-AM (NASA), ENVISAT (ESA) and ADEOS-II (NASDA).