That sinking feeling: It’s the land, stupid!
In November, 2012, a UN climate meeting in Doha yielded the usual crop of scary stories about rising sea levels. Had anyone talked to Bart Shultz they would have gotten some crucial context: Forget rising seas! Sinking land _ caused by slipshod urban planning _ is a bigger, more acute problem.
Shultz retired in 2012 after 20 years as Chair of Land and Water Development at the UNESCO-IHE Institute for Water Education in Delft. He says man-made changes to land use are more harmful than global warming. Worldwide 80 to 90% of new buildings and roads rise up from flood prone areas “resulting in increased damage and number of casualties when an extreme event occurs” such as excessive rainfall, floods and hurricanes. Particularly vulnerable are emerging countries whose combined urban population “is expected to rise from 2.4 billion at present to 4.4 billion by 2050,” he said in a valedictorian speech. In a later Op-Ed piece in the Amsterdam daily De Volkskrant, Shultz added: “We are always told rising sea levels caused by climate change is one of our biggest problems. The reality is totally different and remains barely noted by policy makers and the media though scientific literature has regularly made reference to it.”
Global population growth occurs mostly in coastal areas and flood plains. Using wetlands in the tropics for urban development causes land levels to drop by 10 to 15 cm/year _ far in excess of the recorded rise in sea levels. In the Netherlands, wetlands still sink 1 cm/year. “Since our forebears in the year 1,000 began digging simple drainage ditches these areas have gone down by 4 to 5 meters,” says Shultz. The coastal area of Jakarta has gone down by almost 10 cm per year in the past decade. Bangkok sinks by 4 to 5 cm/year. “As a rule totally insufficient anti-flood measures are taken. If there is a flood, it is blamed on climate change,” according to Shultz. “The focus is always on rising sea levels. Not enough attention is paid to either sinking land levels in coastal and delta regions which account for 90 percent of the problem, or insufficient protection of urban areas against floods.”