Spain02 trends for SE Spain: gridded precipitation, temperature and combined indices (1970-2007)

First different parameters are build for each of the 113 grid points in SE Spain for each year from 1970 to 2007. Seasons were considered as follows: winter from December to February

spring: March to May

summer: June to August

and autumn: September to November. The parameters analysed are:
1. Mean seasonal and annual maximum temperature: average of all daily maximum temperature(Tmax) values in each season and each year
2. Mean seasonal and annual minimum temperature: average of all daily minimum temperature (Tmin) values in each season and each year
3. The mean temperature (calculated as average of Tmax and Tmin) and the diurnal temperature range (DTR, as daily Tmax minus Tmin) are also assesed for each season and year.
3. Total seasonal and annual precipitation: sums of all daily precipitation values in each season each year
4. Combined daily precipitation-temperature indices. First daily mean temperature (Tmean) is assessed as arithmetic average of Tmax and Tmin, and the 25th (T25) and 75th percentiles (T75) are calculated. Days with TmeanT75 are considered ??warm days''. Average precipitation intensity within both warm-wet and cold-wet days is build for each season and year.
The Mann-Kendall non parametric test (Kendall-Tau-b correlation coeffficient) was used to test the existence of significant trends both at 5% and 10% significance levels (using SPSS statistics program). Least squared linear regression was used to estimate the rate of change (slope) in case of significant trend according to Mann-Kendall test.