Monthly Mean Pressure Reconstructions for Europe (1780-1980) and North America (1858-1980), CDIAC NDP-025

This package contains monthly grid-point pressure data for Europe (1780-1980) and for North America (1858-1980). Some of the data are reconstructed values calculated using a principal components regression technique, while others are real pressure values taken from the United Kingdom Meteorological Office (UKMO) data set. Reconstructed values are given up to the time when real grid-point values became available; 1873 for Europe and 1899 for North America, respectively. The European data have 60 grid points spanning 35-70 degrees North and 30-40 degrees East on a 5 X 10 degree latitude/longitude grid. The North American data cover 30-55 degrees North and 60-130 degrees West. The data set includes both monthly and annual mean pressure values at each of the grid points and all data are given in tenths of a millibar and adjusted to mean sea level. The data are derived from both direct and reconstructed sources of monthly mean pressure data. Records of the UKMO were a direct source of monthly mean pressure readings for Europe beginning in 1873 and for North America beginning in 1899. Reconstructed monthly mean pressure values have been calculated for Europe (1780-1872) and for North America (1858-1898) or to the time when real grid-point values became available. These reconstructions use early pressure, temperature, and precipitation data from a variety of sources including World Weather Records, meteorological and national archives, circulation maps, and daily chart series.