China faces dropping crop yields

Climate change could reduce key harvests in China by a fifth if the gloomiest scenarios prove true, according to a study published in Nature.

A team of Chinese scientists say China's climate "has clearly warmed" over the past half century, gaining 2.2 degrees F since 1960. "China experienced explosive economic growth in recent decades, but with only 7 percent of the world's arable land available to feed 20 percent of the world's population, China's economy may be vulnerable to climate change itself," the study warns.

In the most favorable scenario, grain yields by mid-century could remain stable or benefit from the rise in carbon dioxide levels. But in the worst scenario, there could be declines of 4 to 14 percent for rice, 2 and 20 percent for wheat, and 0 and 23 percent for corn in cases where these crops are rainfed rather than irrigated.

The biggest problem could be water stress, amplified by a growing and increasingly wealthy population.

While on water, another study notes that oceans are acidifying 10 times faster today than 55 million years ago when a mass extinction of marine species occurred. Much of the carbon dioxide pollution put into the air is absorbed by the world’s oceans.

Dissolved as carbonic acid, the pollution increases the acidity of the oceans, which is disrupting the marine food chain, especially by making it more difficult for plankton, corals, mollusks, and crustaceans to form their calciferous shells. To avoid substantial damage to ocean ecosystems, deep and rapid reductions of global CO2emissions by at least 50% by 2050, and much more thereafter are needed.

Sorry if we seem to be going on and on about climate change, but you can't well ignore the most pressing problem on the planet today!