Temperature trends in regions affected by increasing aridity/humidity

• Published in: Geophysical research letters Vol. 28; no. 20; pp. 3919 - 3922
• Main Authors: Jones, Philip D., Reid, Phillip A.
• Format: Journal Article
• Language: English
• Published: Washington, DC Blackwell Publishing Ltd 15.10.2001; American Geophysical Union
• Subjects: Earth, ocean, space; Exact sciences and technology; External geophysics; Meteorology; Other topics in atmospheric geophysics; Warming; Potential evapotranspiration; Atmospheric temperature; Arid region; Trend analysis; Desertification; Surface temperature; Atmospheric precipitation; Atmospheric humidity
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2001GL013840

A paper in 1991 claimed that regions affected by desertification experience warming trends relative to neighbouring areas. To assess this, an index of aridity/humidity based on the ratio of annual precipitation to annual potential evapotranspiration totals (P/PET) is developed. This index is used to define regions experiencing increases (and those where the increase is statistically significant) in aridity and humidity. We also consider regions always arid (average values of P/PET <0.5) and always humid (P/PET >2.0). Trends of average annual and summer surface air temperature are then calculated for regions in the various aridity/humidity categories and compared to most of the rest of the world's land areas equatorward of 60°. The results indicate that most of the differences in trends between categories are not statistically significant.