South Asia: Water deficits persist in central India but surplus forecast after April

28 February 2018

THE BIG PICTURE
The 12-month forecast indicates intense water deficits in western Afghanistan, and in parts of northern, southern, and far northeastern India.

Surplus conditions are forecast for Bangladesh and Indian states to the east and west, as well as along India’s west coast from eastern Gujarat through Maharashtra. Exceptional surpluses are forecast in western Andhra Pradesh.

Deficits are forecast in Sri Lanka’s northern half, and surpluses along the southern coast. Mild surpluses are expected in western Nepal with exceptional surplus along the Gandaki River. Moderate deficits are forecast for Bhutan.

FORECAST BREAKDOWN
The 3-month composites (below) show the evolving conditions.

As is apparent in the map progression above, the forecast for India indicates the persistence of intense water deficits in central and parts of southern India through April 2018. After April a dramatic transition to surplus conditions is forecast for a wide belt stretching coast to coast across the country’s middle.

In the next several months, through April, deficits will blanket much of the southern two-thirds of India, punctuated by pockets of both deficit and surplus conditions (pink/purple) as transitions occur. Deficits are expected to be extreme or even exceptional in Madhya Pradesh, western Chhattisgarh, western Karnataka, and eastern Andhra Pradesh. Primarily moderate deficits will emerge in a vast stretch from the Bay of Bengal inland, encompassing Odisha, Chhattisgarh, Telangana, and southern Tamil Nadu. Deficits in northern Sri Lanka will downgrade to moderate. Gujarat, in western India, will see conditions of both deficit and surplus, as will the western stretch of the Krishna River and much of the Penner River Basin.

Exceptional surplus conditions will persist throughout Bangladesh and India states to the east, as well as in eastern Jammu and Kashmir in India’s far north. Severe to exceptional surpluses remain in the forecast for West Bengal, and throughout Nepal.

Exceptional deficits will nearly disappear in Afghanistan, but moderate to severe deficits will continue to emerge throughout much of the country.

From May through July a transition from widespread deficit to surplus is forecast for a vast belt across India’s middle, stretching from eastern Gujarat on the Arabian Sea to West Bengal on the opposite coast. Surpluses are expected to be moderate to severe with a block of exceptional surplus in Maharashtra between the Godavari and Tapi Rivers. Surpluses will emerge along the Godivari and Krishna Rivers, and exceptional surpluses will re-emerge in western Andhra Pradesh. Intense deficits are forecast to emerge in India’s far northeastern states.

Conditions in Bangladesh will transition from exceptional surplus to near-normal, surpluses will persist in western Nepal, and moderate deficits will emerge in Bhutan. Deficits will persist throughout most of Afghanistan and will intensify in the southwest, becoming exceptional. Moderate deficits will emerge in northern Pakistan.

The forecast for the final period – August through October 2018 – indicates a downgrade to mild surplus across central India, and a pattern of deficits in Afghanistan similar to the forecast in the prior three months.

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

IMPACTS
The UN refugee agency is warning that 100,000 Rohingyas who fled Myanmar to camps in southeastern Bangladesh are in danger from flooding and landslides when the monsoon season begins in April. Around 570,000 refugees occupy a sprawling settlement - the world's largest refugee camp - in Kutapalong and Balukhali. In addition to environmental stress from the sheer number of inhabitants, many trees were felled to make space, leaving the land even more susceptible to water erosion. Experts estimate that nearly one-third of the settlement could be flooded.

The humble chickpea, source of protein for 20 percent of the world's population, is enjoying rock star success due to the increasing global popularity of hummus, a longtime staple of Middle Eastern cuisine. But drought in India, which is the largest producer of chickpeas, has caused hummus prices thousands of miles away in British grocery stores to jump by 12 percent over last year. Though the Indian crop is destined primarily for the domestic market, dry conditions have forced India to look outside its borders for the legume, reducing global supply and driving prices up.

Domestic chickpea strains have low genetic diversity, threatening their adaptability to environmental change. Their wilder relatives in southeastern Turkey, however, hold promise with genetic resources that could be used to breed drought-resistant and heat tolerant varieties.

India’s Supreme Court has decreed that, for the next 15 years, water from the Cauvery River will be allocated in fixed share amounts to several southern regions, potentially ending a 200-year dispute. The state of Karnataka had its allocation raised to alleviate drought and to provide drinking water for its fast-growing capital, Bengaluru, home of Indian and US tech giants. Tamil Nadu, with its greater groundwater resources, had allocation reduced. Disputes over reservoir holdings in Karnataka have arisen many times over the years, erupting in violence as recently as 2016.

Prolonged drought - the longest in four decades - has prevented many farmers in the Karnali and Seti zones of western Nepal from growing anything for the past three years. Up to a quarter of the population in some villages has left for India in search of work.

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