Rising sea levels and not rising temperatures are the main threat from climate change for people in the UK, according to an expert.
Professor Mark Maslin, director of the Environmental Institute at University College London, said that although adapting to warm wet winters and dry hot summers would not present too many difficulties to the UK population, coping with rising sea levels was another matter.
Predictions indicate that sea levels will rise by 80 cm by 2080. Any time after 2030, the Thames barrier could be breached and London flooded, he told an informal debate on climate change and water held last week at Chatham House, London (www.chathamhouse.org.uk).
In this scenario, Professor Maslin predicted that 65 tube stations would flood and the ensuing catastrophic disruption to the city would be enough to prompt a global recession.
Global average (near) surface temperatures have been rising steadily for the past three decades and will continue to do so, he said. The need to reduce carbon emissions and pursue local adaptive strategies, which include water conservation, was unequivocal.
“Between 2000 and 2030 we will emit more CO2 than we have ever done in the whole of history,” said Professor Maslin. Getting a collective global agreement on a 2012 successor to the Kyoto protocol was crucial. In this respect, he added, “much hangs on the outcome of the US presidential elections.”
Although countries at higher latitudes will get hotter and wetter, Australia, southern Europe, much of sub-Saharan Africa, Brazil, Mexico, and Central America will get less and less rain. Predictions here indicate that the number of people living in “water poverty” will increase from 1.5 to 3 billion over the next 80 years, said Dr Richard Taylor, a hydrologist at University College London and Makere University in Uganda.
Agriculture accounts for two thirds of global water demands and even with improved irrigation methods the reduction in crop production will result in food insecurity.
Much more effort should be made to trap water—in dams, retention ponds, and reservoirs—Dr Taylor said. He warned that the water tables in India, southern Spain, certain African states, and the United States were finite and dropping steadily.
How people respond to water shortages will be crucial, not only in terms of conservation and more efficient use but also in agreements between countries on how to mange water resources.
“Those who will suffer most from water scarcity are least able to respond and adapt to change,” said Dr Taylor. Rich countries needed to do more to help poorer ones manage their water resources efficiently and respond to crises such as major flooding. Increased global cooperation was also needed on the growth and trade of agricultural products, in a way that protected the poorest and most vulnerable populations.
Both speakers emphasised that the potential of desalination to solve water shortages was not a realistic option for most countries because it was too energy intensive and too expensive.
The predicted massive rise in global population was “the elephant in the room,” said Professor Maslin. Given our limited resources and water supplies, “We have to ask ourselves what a sustainable population for the planet is, and at what level of development” he added.