Towards identifying areas at climatological risk of desertification using the Köppen–Geiger classification and FAO aridity index

We coupled the information obtained from the Köppen-Geiger (KG) climate classification and the FAO Aridity Index (AI) to provide an overview of the most evident global changes in climate regimes from 1951-80 to 1981-2010. Based on a set of sixteen auxiliary variables and special conditions derived from mean temperature (TM) and precipitation (RR) values, KG classifies climate into five major classes (arid, tropical, temperate, continental, polar), that are further sub-categorized for a total of thirty classes. AI is based on the ratio between the annual total RR and potential evapo-transpiration (PET) and classifies climate into eight classes, from desert to humid. To compute the indicators, we used a combination of two datasets on a 0.5˚ x 0.5˚ global grid: RR from Full Data Reanalysis (version 6.0) provided by the Global Precipitation Climatology Centre (GPCC), TM and PET provided by the Climate Research Unit of the University of East Anglia (CRUTS version 3.20). Both KG and AI agree: from 1951-80 to 1981-2010 the cold areas decreased, whilst the arid areas globally increased except of the Americas. Some hot spots at high desertification risk have been detected: North-Eastern Brazil, Southern Sahel, Zambia and Botswana, Southern Spain, North Eastern China, Central India, and Southern Argentina. We also discuss the change from continental to temperate climate in Central Europe, the shift from tundra to continental climate in Alaska, Canada and North-Eastern Russia, and the widening of the tropical belt.

SPINONI Jonathan;  NAUMANN Gustavo;  CARRÃO Hugo;  BARBOSA FERREIRA Paulo;  VOGT Juergen; 

2014-09-18

WILEY-BLACKWELL

JRC83589

0899-8418,   

http://onlinelibrary.wiley.com/doi/10.1002/joc.4124/abstract,    https://publications.jrc.ec.europa.eu/repository/handle/JRC83589,   

10.1002/joc.4124,