fect. Excessive snow in the early part of winter tends to reduce solar radiation in winter (up to four times compared to bare ground) by increasing the surface albedo, thus resulting in the persistence of colder temperatures (and possibly additional snow anomalies). Thus, holding other processes constant, excess snowfall gives rise to a positive feedback.

In particular, positive snow anomalies over the Eurasian continent in winter and spring lead to colder ground temperatures in the following summer and hence anomalously weak meridional temperature gradients, because a substantial fraction of the solar energy available in spring and early summer would go to melting the snow and evaporating water from the wet soil. This lower land-ocean temperature contrast would presumably lead to below-normal monsoon. The entire scenario would be reversed when winter and spring Eurasian snows are below normal precipitation.

General circulation modeling sensitivity experiments substantiate observational evidence of an inverse snow-monsoon relationship.12 In analyzing the relative role of SST variations and land surface processes on the interannual variability of the Asian monsoon system, it is recognized that the former plays a dominant role.

The quasibiennial aspect of monsoons has been investigated, and it has been noted that monsoons play an active role in determining the anomalous state of the warm-water pool in the western Pacific in the following autumn and winter seasons.13 Studies have also suggested an intriguing three-way interaction between Eurasian snow cover, monsoon, and ENSO.14

Forecasting Seasonal to Interannual Variations in Northeast Brazil

The northeastern part of Brazil (in particular, the state of Cear á) is semiarid, has a rainy season from February to April, and is subject to wide rainfall fluctuations from year to year. Throughout Brazilian history, severely dry periods have been marked by severe social dislocations and mass migrations, which have affected the 30 million people of Ceará and the entire social and economic fabric of Brazilian culture.

Statistical correlations of rainfall with climatic indices15 have indicated that Ceará's rainfall is correlated with SST in both the Atlantic and the eastern Pacific. Realizing the vulnerability of its economy to such interannual climate fluctuations, the state of Ceará, in conjunction with the federal government, established an institute called FUNCEME (Funda ção Cearense de Meteorologia e Recursos Hídricos—Ceará's Foundation for Meteorology and Hydrological Resources) to advise the state on the proper actions to take in anticipation of adverse climatic conditions. FUNCEME has published a monthly information bulletin (Monitor Climático) since 1987 that gives monthly global climatic data, ENSO predictions, and local precipitation and hydrological data.

FUNCEME maintains programs addressing both long- and short-term is-



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