Projected changes in modified Thornthwaite climate zones over Southwest Asia using a CMIP5 multi‐model ensemble

Abstract

Climate change is known as one of the key challenges of the 21st century for sustainable agricultural development over Southwest Asia. However, not much is known about the way that climate changes might affect precipitation, temperature, and climate zones as their consequence over Southwest Asia. Here we have analysed probable changes in modified Thornthwaite climate zones by using monthly temperature and precipitation data from 320 meteorological stations during the historical period of 1971–2015, as well as the future projections of 17 GCMs (General Circulation Models) outputs under the RCP4.5 and RCP8.5 scenarios in two future periods, 2041–2070 and 2071–2100. The CMIP5 climate projections were bias corrected using the correction factors derived in the historical period and applied to simulate future climatic conditions over Southwest Asia. Results derived from multi model ensemble projections of precipitation and temperature indicated that the regional mean annual temperature by the future period of 2071–2100 is expected to increase by 2.4 and 3.8°C, under RCP4.5 and RCP8.5, respectively. Also, except for the southern and eastern parts of the Arabian Peninsula, by 2071–2100, the mean annual precipitation would significantly decrease by on average 6.2 and 7.5%, under RCP4.5 and RCP8.5, respectively. Computing climate types based on averages from three climatic periods (1971–2015, 2041–2070, and 2071–2100) showed that Southwest Asia tends to become warmer and dryer. For example, by the end of the 21st century, the percentage of the area occupied by the torrid‐arid climate type (which already covers 13.8% of the total area) would be 29.3 and 36.4% under RCP4.5 and RCP8.5, respectively. These changes are important because they would definitely have profound ecological, hydrologic, and social consequences and may affect the basic components of sustainable agricultural systems like crop and livestock productions.

Larger Carpathian region climate according to Köppen, Feddema and the Worldwide Bioclimatic Classification System methods

“…According to the Essenwanger (2001) criteria Feddema's method is the most suitable method for analysing the climate structure of the LCR because it needs less input data and is a simpler method than the WBCS. Also, the terminology and even intervals make it easier to interpret the results of the Feddema method than the other methods (Rahimi et al ., 2019). It is also important that the Feddema method can be rescaled in order to characterize the climate spatial structure not only on the meso‐β scale (20–200 km), but also on even smaller scales (Ács, 2017).…”

“…Feddema's method together with the WBCS were developed partly in the 21st century and, as such, can be treated as up‐to‐date methods, however, it has been used only in a few cases (Grundstein, 2008; Elguindi et al ., 2014; Ács et al ., 2017; Breuer et al ., 2017; Skarbit et al ., 2017; Rahimi et al ., 2019). Feddema revised Thornthwaite's method partly according to Thornthwaite's suggestions in the Thornthwaite (1948) paper.…”

The relationship between the normalized difference vegetation index, rainfall, and potential evapotranspiration in a banana plantation of Venezuela

“…The P and T time-series present no missing data and their consistencies were evaluated in terms of data quality and homogeneity as explained in (Blesić et al, 2019). The potential evapotranspiration (PE) (in mm month -1 ) was estimated using Thornthwaite's equation (Rahimi et al, 2019), where T is used as a unique input.…”

Compound Effects of Climate Change on Future Transboundary Water Issues in the Middle East

“…Middle East climate studies based on global climate model (GCM) realizations from previous phases of the Coupled Model Intercomparison Project (CMIP) suggest that magnitude and spatio–temporal patterns of hydroclimatic variables are to change (Evans, 2009; Rahimi et al., 2019; Tabari & Willems, 2018; Vaghefi et al., 2019). The possible future changes reported in these studies include spatial variability in precipitation trend, expansion of torrid‐arid climate zone, and increase in dry and hot periods in parts of the region.…”