Too Much CO2 Hurts Crops, Damages Algae

Posted on May 10, 2011


Two recent studies about the affect of CO2.

Corn and wheat decline under climate change

The IPCC predicted an increase in agricultural production in the short run matching the increase of greenhouse gases, particularly CO2, in the atmosphere.  Where other factors are present, CO2 can aid plant growth.

However, David Lobell, agricultural scientist from the Stanford University, Palo Alto, California, and some colleagues recently completed an analysis of agricultural records from 1980 to 2008 to try to measure the early effects of climate change.  They examined particularly corn, rice, wheat and soybeans which together represent 75% of what feeds the human race.

In respect of rice and soybeans, the team found no increase, but no decrease either in agricultural production.

However, corn declined by 3.8% and wheat declined by 5.5% over the period.  The IPCC had apparently been too optimistic.

One of the study’s conclusions was that a rise in temperature of 1o C. (1.8o F.) would tend to lower yields by 10% in countries outside the high latitudes.

“It’s a frustration having to always answer questions about the future and having everyone think of climate change as something in the future.” David Lobell said.  “It’s not something we have to anticipate. It’s something we have to learn from and deal with right now.”

See Climate Change Already Hurting Agriculture – Science Now

Coccoliths will dissolve, algae will suffer in acidifying oceans

Algae is important to earth’s carbon-oxygen cycle and thus our ecosystem as a whole.  Encapsulating and protecting a number of species of algae are coccoliths, very small shells of calcium carbonate which form even in waters low in calcites.  However these shells, as a recent study makes clear, are highly sensitive to ocean acidification.

Ocean acidification is the companion disaster to climate change, arising from the same increase of carbon dioxide in the atmosphere.  When the ever-increasing amounts of CO2 dissolve in the ocean, it becomes carbonic acid.

Tue Hassenkam of the University of Copenhagen who is part of the NanoGeoScience research group which conducted the recent study on coccoliths says,  “It turns out that the shell falls completely apart when we do experiments in water with a pH value that many researchers believe will be the found in the world oceans in the year 2100 due to the CO2 levels.”

Bad news for earth’s carbon-oxygen cycle and all of us earthly inhabitants who depend on it.

See Ocean Acidification:  Carbon Dioxide Makes Life Difficult for Algae – Science Daily

Posted in: climate change