CLIMATE change will sow confusion and concern as it unfolds across South Asia in coming decades. Home to a quarter of the world's population, this vast region will be hit harder than just about anywhere else. Sudden flooding, storms, droughtsand other hazards will upend lives, livelihoods, and economies.
As this grim future takes shape, the price of global inaction is rising each year. Up to 9% will have been stripped annually from South Asia's economy on average by 2100 if no further action is taken globally on climate change, says a new report by the Asian Development Bank, Assessing the Costs of Climate Change and Adaptation in South Asia. There's an outside chance of those losses blowing out to 24% given the uncertainty surrounding climate change's future impacts.
What can be done? The region's countries have taken steps to cushion the impact of a warming world, but bolder action is needed. Given the slow pace of global mitigation efforts, the worst-case scenario of huge economic losses might end up being South Asia's future by default.
While only global action will halt climate change, countries should not wait on it before taking adaptive measures. They can be as straightforward as placing sand-filled geotextile bags along riverbanks to stall erosion as happened recently in low-lying Bangladesh, where an area up to a third the size of metropolitan Chittagong is swallowed annually. Or they can be more wide-ranging, like a recent initiative of the United Kingdom government, The Rockefeller Foundation and ADB to boost climate resilience at 25 cities in Asia by helping to integrate climate risks into city plans and develop resilient infrastructure.
Those efforts must now be mainstreamed into national development plans, with governments, the private sector and civil society working together. Moreover, as climate change ignores national borders, South Asia's countries must respond cooperatively through a regional framework to promote technology transfer, dialogue, and sharing of best practices.
The sooner this happens, the better. Though some areas may benefit temporarily from a see-sawing climate, overall it will be very bad news for South Asia's 1.5 billion peopleif nothing is done globally. Maldives and Nepal would lose 12.6% and 9.9% of their economies respectively each year by 2100. Losses in Bangladesh would tally 9.4%, India 8.7%, Bhutan 6.6% and Sri Lanka 6.5%.
But the damage would be significantly less if global action is taken on climate change, with just 2.5% culled from the region's potential gross domestic product by the end of the century.
Obviously this best-case scenario is preferable, particularly in South Asia which due to its geography, huge population and widespread poverty faces acute climate risks. Extreme weather events will become a more destructive fact of life. Droughts will be longer and more intense, while storm surges from rising sea-levels and floods from heavier rain will be constant threats. Flooding will also occur as lakes formed by melting glaciers burst their banks, and frequent landslides will dump debris into rivers, endangering lives and infrastructure.
This will make it tougher for South Asia's economies to achieve rapid growth, but the human toll is even more alarming. Those likely to suffer most are the 600 million South Asians living in absolute poverty - more than half the world's total poor. Escaping from poverty will become an even more daunting challenge, as many poor people depend for their livelihoods on climate-sensitive sectors like agriculture, forestry, and traditional fishing.
Bangladesh is one of 10 countries most at risk from climate change. Extreme weather events, heat stress, and shorter growing seasons will slash crop yields. Coastal residents will confront flooding and storm surges as sea levels rise. Dependence on agriculture and a low rate of rural electrification will magnify the challenges.
Across the subcontinent, impacts will include higher incidence of diseases like dengue, patchier energy supply and higher electricity bills, erosion and reduced household water stocks. Hard-hit communities may have to relocate to survive.
These are just some of the climate shocks that will jolt South Asiain coming years. Just how hard they hit will depend, to a degree, on global action - or lack thereof - on climate change. But that only makes the case even more compelling for better climate change adaptation. Just a few of the many adaptive options available include using drought, flood and salt-resistant crop varieties, reforming water policy, and building better drainage systems.
And the time for action is now. Because the longer South Asia waits to step up its adaptive response, the more it will cost.
If temperatures and sea-levels rise appreciably amid global inaction, the annual average cost of climate change adaptation could hit $73 billion between now and 2100, but only $41 billion under a more optimistic scenario. Upgrading adaptation from today will make the cost more manageable, no matter what happens globally.
South Asia has made huge strides recently in boosting prosperity and reducing poverty. It would be a tragedy if climate change were allowed to roll back those gains.
The writer is ADB Vice-President for Knowledge Management and Sustainable Development, Asian Development Bank