Leading scientist warns of impacts of climate change in Asia
Natural ecosystems are set to change dramatically in Asia and humans will not escape the consequences, warns Rodel D. Lasco of the Intergovernmental Panel on Climate Change
‘Practically every spot on the Earth has warmed,’ said Dr Rodel Lasco, World Agroforestry Centre Philippines country coordinator, presenting the key findings on climate change in Asia from the fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) at the 2015 Green Seminar Series—‘Finding solutions towards climate-resilient communities’—at the University of the Philippines Los Baños Climate Risk Studies Center and School of Environmental Science and Management, 18 March 2015.
‘Clearly, climate change does not only affect natural ecosystems but also the lives of people’, he pointed out. Dr Lasco is the lead author of the Asia chapter of the IPCC’s Working Group 2 , which looks at the impacts of, and adaptation and vulnerability to, climate change. He emphasised that there is a consensus among scientists that global temperatures are increasing and rainfall patterns and amounts will be hard to predict.
‘This translates into uncertainty regarding future freshwater availability in most parts of Asia’, he said. ‘This will be exacerbated by the lack of good management and increase in water demand owing to population growth and higher standards of living. This is likely to worsen water scarcity throughout the region’.
The uncertainty extends to predictions regarding tropical cyclones, the frequency of which might actually decrease or perhaps remain unchanged. However, Dr Lasco noted that it’s likely that those cyclones that do occur will show an increase in maximum wind speed and rainfall, meaning greater likelihood of ‘super storms’.
Furthermore, coastal communities will probably experience severe impact from the rising sea-levels in the Asian Arctic, which, combined with changes in permafrost and longer lengths of ice-free seasons, will cause greater erosion of beachside land while coastal freshwater swamps and marshes will suffer from saltwater intrusion. Low-lying coastal rice fields, too, are in danger, especially those in the Mekong Delta, where nearly a third of productive land is slated to be salt-affected. Farmers there are already seeing their fields becoming unusable except as fish farms.
Out at sea, ocean acidification and warming will increase damage to coral reefs while warm-water species might move towards more temperate areas and marine biodiversity generally in the tropics may decrease if temperatures exceed tolerable limits. This will likely cause strains on seafood supplies to increasing populations.
Back on land, shifts in the reproductive cycles, growth rates and distribution of plant and animal species have already been observed. Projections show boreal trees invading the treeless arctic, however, the impact of climate change on the vegetation of the lowland tropics is still poorly understood and hence planning for more adaptive food-crop species in particular biophysical zones is limited, with potentially dire consequences for humans.
‘Declines in agricultural productivity owing to climate change will mean greater food insecurity for the growing population’, he said.
Most models show higher temperatures leading to shorter growing periods and lower rice yields although losses because of heat stress may be offset in part with carbon-dioxide fertilization enhancing plant growth of rice and other crops.
How can we adapt?
‘Let’s just adapt now, for now’, urged Dr Lasco. The main thing is to address the current climate risks and eliminate the “adaptation deficit”, that is, the difference between what has actually been done and what else could have been done. ‘Governments should focus on adapting to the climate now’.
He suggested that integrated water management, including technologies and practices that save water or increase water productivity and reuse, could help in adapting to climate change right now, even in areas that currently experience an abundance of water.
People can also prepare for extreme tropical cyclones by improving forecasting and early-warning systems. ‘Communities should know when the events are coming and what to do when they come’, he said.
As for endangered species, although the Philippines has mandated protected areas, most are only protected on paper and not in practice. ‘The Philippines has lost 50% of its forest cover even without climate change,’ pointed out Dr Lasco. ‘So, habitat destruction must first be addressed before looking towards adapting or shifting protected areas in response to climate change’.
But much more work needs to be done, and quickly. More studies need to be carried out of observed changes in climate and their impact in North, Central and West Asia, as well as improving projections for precipitation and water supply throughout the region. Health studies which look at the effects of the interaction between heat and air pollution are also needed.
‘Particular studies in the tropics should focus on the temperature dependence of carbon fixation by trees and the thermal tolerances and the capacity of plants and animals to adapt to climate change’, recommended Dr Lasco.
It’s clear that much needs to be done, now, if we are to adapt to the future that we have helped create.
This work is linked to the CGIAR Research Program on Forests, Trees and Agroforestry