Human-induced warming reached approximately 1.0 ± 0.2 °C above pre-industrial levels in 2017, increasing at 0.2 °C ± 0.1 °C per decade. Climate change exacerbates the water cycle and is particularly obvious in arid inland regions. Hydrological responses to global warming are becoming deeply concerning for scientists and society.
Central Asia is one of the most arid regions. Despite the prevailing aridity, agriculture is the primary sector in Central Asia and about 90 % of water abstractions are used by agricultural sector. Considering the current water balance conditions and rising temperatures, changes in crop water requirement and water supply (represented by precipitation) are expected.
Targeted the above questions, researchers from State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, analyzed the future changes in precipitation and temperature, and predicted crop water requirement(CWR) under warming scenarios of 1.5°C and 2.0°C by using 10 GCM outputs and CRU dataset.
The research results indicated that, Central Asia is more sensitive to climate change compared to the global average, the temperature is predicted to rise by 1.7 °C and 2.6 °C and precipitation to increase by 9 % and 12 % in global warming scenarios of 1.5 °C and 2.0 °C, respectively. The average crop water requirement is expected to increase by 13 mm and 19 mm, respectively, under the global warming scenarios of 1.5 °C and 2.0 °C.
What’s more, a widening gap between water supply and water demand is expected compared to the historical period (1976–2005) under global warming scenario of 2.0 °C. Under global warming of 2.0 °C, the anticipated water gaps between precipitation and CWR are projected to increase by 2.8 × 108m3 and 1.5 × 108 m3 for the rain-fed north Kazakhstan region and the irrigated Fergana region while the increase of precipitation could able to meet the increase in CWR under global warming of 1.5 °C.
Investigating the water balance for major planting areas in water-limited Central Asia could provide a scientific basis for its sustainable development. The research results are published on Agricultural Water Management, entitled Agricultural water demands in Central Asia under 1.5 °C and 2.0 °C global warming.
Article link: https://www.sciencedirect.com/science/article/abs/pii/S0378377419305426
Contact: LIU Jie, Xinjiang Institute of Ecology and Geography