AN HISTORICAL RECORD OF EVAPORATION LOSSES SINCE 1815 CALCULATED USING LONG-TERM OBSERVATIONS FROM THE RADCLIFFE-METEOROLOGICAL-STATION, OXFORD, ENGLAND

The paper presents and discusses an historical series of evaporation l osses, both potential and actual, and differences between precipitatio n and evaporation. The series were calculated using temperature and ra infall records for the Radcliffe Meteorological Station (Oxford) where an unbroken series of daily observations began in 1815. it is demonst rated that during the last decade potential evaporative losses have be en above the long-term average; differences between precipitation and potential evaporation, an index which shows availability of water for runoff, have noticeably declined. These trends have been particularly marked in summer months. The summer soil moisture deficits observed du ring the last 20 years have been the largest on record; moisture defic its have persisted into the late autumn delaying seasonal recovery in river flow. (C) 1998 Elsevier Science B.V.