Central Asia: Water surpluses forecast in the Ural River Basin

November 23, 2016

The Big Picture
The 12-month map (below) indicates widespread water deficits, including exceptional deficits (greater than 40 years) forecast in Arctic Russia from the White Sea to the Central Siberian Plateau. Surpluses are forecast in the Ural River Basin in Kazakhstan, in central Kazakhstan, and in eastern Kyrgyzstan. Deficits are forecast for much of Turkmenistan, Uzbekistan, and Tajikistan.

Impacts
Cars looked like giant marshmallows as 32 centimeters (12.6 inches) of snow buried them in Almaty, Kazakhstan, home to over 1.5 million people. Drifting in the nearby foothills of the Trans-Ili Alatau mountains reached nearly twice that depth - 60 centimeters (23.6 inches). It was an unusual amount of snowfall for the southern city, whose seasonal average is between 15 and 20 centimeters (5.9-7.9 inches), requiring 1,300 snow removal workers and 75,000 tons of de-icing compound. The blizzard closed the Usharal-Dostyk highway in Almaty region and the Noviy Obkhod-Kordai motoway in Zhambyl region.

Forecast Breakdown
The 3-month composites (below) for the same 12-month period show the evolving conditions in more detail.

The vibrant and complex patchwork visible in each of the 3-month maps for Central Asia indicates that water anomalies – both drier than normal and wetter than normal – blanket the 12-month forecast, with relatively few areas predicted to have normal conditions.

Comparing, first, observed conditions August through October with the forecast for November through December, it is apparent that drier than normal conditions will continue to dominate much of northern Russia from the White Sea to the Central Siberian Plateau with deficits ranging from moderate (10 to 20 years) to exceptional (beyond 40 years). Deficits on the Yamal Peninsula will diminish in extent and severity, transitioning away from exceptional deficit to primarily moderate deficit. A vast area of exceptional deficits (dark red) will persist between the Yenisei and Ob Rivers, with both deficits and surpluses west of the Ob to the Irtysh River.

The Ural River Basin in northwestern Kazakhstan will continue to experience exceptional surplus (dark blue) November through January along with areas of both exceptional deficit and surplus (purple). Surpluses will continue to emerge in a north/south line through central Kazakhstan from Kishkenekol in the north through Karagandy Region in the south. Moderate surpluses are expected along the Syr Darya River. Moderate deficits are forecast for eastern Turkmenistan; surpluses and deficits in Tajikistan; and primarily surpluses in Kyrgyzstan.

From February through April exceptional deficits in northern Russia will diminish in extent, though moderate to extreme deficits will persist with pockets of exceptional deficits. The extent of surpluses in Kazakhstan will also diminish but exceptional surpluses will persist in the Ural River Basin and in central Kazakhstan. Widespread moderate deficits are forecast for Turkmenistan, Uzbekistan, and southern Tajikistan.

The forecast for the final three months, May through July, shows persistent deficits in northern Russia and emerging surpluses near Novosibirsk, Russia between the Ob and Tom Rivers.

(It should be noted that forecast skill declines with longer lead times.)