Uzbekistan calls itself the sunny country with more than 270 sunny days per year. It could equally be called the dry country. 70% of the country is desert and the rest doesn’t get much more rain. In 2005 the country had a water deficit of 2,000m3 and this is projected to increase as the climate warms.
About 10% of the country is fertile river valleys whose bountiful harvest is entirely dependent on irrigation. Almost 90% of the countries surface water is currently used for irrigation. Climate change will see the countries two main climate zones dry/tropical and moderate to shift to 150 – 200 km to the North. Total precipitation is projected to increase across most regions in Uzbekistan although the dry desert and steppe regions are predicted to decrease. However rainfall during the key summer growing months will be lower while average temperatures are likely to rise by as much as 3 to 4C and possibly more over the next 40 years. This will cause evaporation and transpiration rates to increase, more than outweighing any increases in precipitation and the water deficit is expected to rise to 13,000 m3 over the next few decades. Under such a scenario crop yields are predicted to decline by up to 50% if no adaptation measures are put in place.
However measures could be relatively easily introduced which would help famers adapt to at least moderate reductions in the availability of water. Many of the crops currently grown, especially cotton are particularly water intensive so switching to less thirsty crops is one adaptation. Most of the irrigation infrastructure was constructed during the days of the Soviet Union and is old and badly maintained causing t water loses of between 50 & 80 %. And nearly all fields are irrigated using techniques which have remained largely unchanged for thousands of years. Water is channelled over the field using a series of ditches. This is extremely inefficient and up to 70% of the water is wasted. Switching to a system of drip irrigation using pipes to apply the water directly to the roots of the plant can increase the efficiency to 90%. However such systems involve a high capital outlay and often require more energy to operate pumps etc. and there is little evidence of integrated government action to begin the process of adaptation. However their becomes a point when it is no longer possible to adapt. It becomes simply too hot for crops to grow adequately and the land turns to desert.
Much of Uzbekistan’s water is sourced from rivers which rise in Kyrgyzstan and Tajikistan and disputes over water have contributed to already fractious relationships between the neighbours. As the water flows in these rivers decline tensions will only heighten.
Soil salinity as a result of centuries of irrigation is also a serious problem in Uzbekistan with 6 million people already affected. Climate change will make it worse. Increased evaporation will cause more salts to be deposited into the soils. Decreasing water resources will lead to a deterioration in water quality with ground water becoming increasingly saline. Salty soils require more water for irrigation and reduce yields.
Of course no discussion of environmental issues in Uzbekistan could fail to mention the Aral sea. A prime example of the consequences of trying to master nature. Once the 4th largest lake in the world it’s surface area has decreased by 60% as a result of diverting its source waters for irrigation. At the same time it was used as a dump for sewage, industrial waste and pesticides. Water levels have decreased to such an extent that the lake has split into two and land where its waters once washed has transformed into a salt desert called Aralkum.
Climate Change is a grave danger to Uzbekistan. Even moderate increases of temperature will pose serious challenges particularly for the agricultural sector. More extreme rises will bring into question the very existence of the country itself as the cities become scorching ovens and crops turn to dust. Millions will be forced from their land and society will begin to break down. As water resources dwindle tensions between neighbouring countries could easily spark war. A frightening prospect yet such a scenario will become inevitable if the world fails to act on climate change.