This is the first installment of a five-part series by Bill Chameides on How We Know Humans Cause Global Warming.
1. A 175-year-old Puzzle
2. What Chemistry Tells Us
3. Causes of Past Climate Change
4. The Medieval Warming Period
5. The Only Explanation Left
Most people these days accept that our planet is warming, but some find it hard to believe that mere humans could cause such a large-scale global change. How do we know that the warming is due to human activity? How can we be so sure?
Today’s post is by Bill Chameides, Chief Scientist at Environmental Defense.
The hurricane season began on June 1, and we are all waiting with some dread to see what this year will bring. Will it be a relatively mild season like last year, a devastating one like 2005, or something in between? An ominous sign is that we have already seen two tropical storms in the region: Andrea, which formed almost a month before the season began, and Barry, which formed on the first day of the season.
Last week I read that Oman was hit by Tropical Cyclone Gonu. ("Hurricane", "typhoon", and "cyclone" are all names for the same thing.) I know that Asia and Australia are regularly hit by tropical storms, but the Arabian Peninsula? Is that normal? I didn’t know, so I decided to do a little investigating. Here’s what I learned.
Guest blogger Lisa Moore, Ph.D., is a scientist in the Climate and Air Program.
There’s always something new in climate change research. This week, scientists described the risks of geo-engineering, proposed an efficient way to reduce Arctic climate change, and discussed options for decreasing deforestation in developing countries.
Guest blogger Lisa Moore, Ph.D., is a scientist in the Climate and Air Program.
Last week, Bill summarized two new studies about carbon dioxide levels in the atmosphere and ocean. This week brought three very different topics: hurricanes (quite timely, since today is the first day of the Atlantic hurricane season!), global rainfall patterns and rainbow trout.
If you’re concerned about hurricanes and global warming and you’ve been reading the newspapers and magazines, you are probably confused.
Perhaps in an effort to be “balanced,” most stories in the media these days present a muddled picture. Cornelia Dean’s piece in the New York Times is a good case in point: a scientific paper is cited claiming a connection; another is cited claiming the opposite. The implication is that the science is inconclusive.
If you’re an avid follower of the news, you may have heard of a company called Planktos that’s trying to fight global warming and make a profit at the same time through a process called "ocean fertilization".
The concept is simple: phytoplankton (tiny one-celled algae) take up carbon dioxide (CO2) during photosynthesis. Fertilizing the ocean encourages growth of phytoplankton, and increases the rate at which CO2 is consumed – presumably leading to less CO2 in the atmosphere. Since ocean photosynthesis is often limited by lack of iron, the idea is to dump iron into the ocean and watch the phytoplankton bloom. Planktos sees this as an economic opportunity: Increase CO2 uptake in the ocean, and sell it as an offset to carbon emitters. (I talked more about how offsets work in a previous post on land-based offsets.)
Ocean fertilization may sound like a good idea, but it has some very serious problems. Here’s why.
