Most Popular Posts
Categories
- Biodiversity (92)
- Climate change (172)
- Community-based conservation (81)
- Economics and conservation (136)
- Endangered species (211)
- Fresh water (48)
- Habitat (221)
- Invasive species (93)
- Marine (123)
- Monitoring (230)
- Restoration (150)
- Socio-political issues (176)
- Tools and technology (101)
Archives
- February 2010
- January 2010
- December 2009
- November 2009
- October 2009
- September 2009
- August 2009
- July 2009
- June 2009
- May 2009
- April 2009
- March 2009
- February 2009
- January 2009
- August 2008
- July 2008
- June 2008
- May 2008
- April 2008
- March 2008
- February 2008
- January 2008
- December 2007
- November 2007
- October 2007
- September 2007
- August 2007
- July 2007
- June 2007
- May 2007
- April 2007
- March 2007
- February 2007
- January 2007
Nov
18
2009
Ocean absorbs billions of tons of man-made carbon each year
Researchers have pieced together a history of the ocean’s absorption of industrial-era carbon, published this week in Nature.
The ocean sucks up a large fraction of carbon dioxide emissions, but figuring out exactly how much has been difficult. A team used records of ocean temperature, salinity, chemical tracers, and other data, as well as models of ocean mixing, to estimate the amount of carbon from anthropogenic sources entering the ocean since 1765.
As of 2008, the ocean contained 140 billion metric tons of anthropogenic carbon and was taking in 2.3 billion tons more per year, the researchers report. The amount absorbed annually has shot up over the last half-century, but the rate has been increasing slightly less quickly since the 1980s. Because of large uncertainties, that recent slowdown may not be statistically significant, says co-author Timothy Hall of the NASA Goddard Institute for Space Studies. However, he says, it is consistent with expectations that the ocean’s ability to take up carbon dioxide will eventually saturate.
The team also found that the land turned from a carbon dioxide source to a sink around the 1940s. One possible explanation is that the increased carbon dioxide in the atmosphere is providing more “food” for photosynthesis, leading to a fertilization effect, says Hall. – Roberta Kwok
Source: Khatiwala, S., Primeau, F., & Hall, T. (2009). Reconstruction of the history of anthropogenic CO2 concentrations in the ocean Nature, 462 (7271), 346-349 DOI: 10.1038/nature08526
Image © MichaelJay, iStockPhoto.com
Filed Under Climate change, Marine |
Email This Post