19 Dec 2012
Holiday Un-Cheer: New Science in Climate Change
New reports this fall reveal that climate change is hitting faster and harder than scientists predicted.
NOAA reports record loss of Arctic ice cover this year. Researchers reveal in the journal Environment Research Letters that sea levels are rising 60% faster than expected.
The United Nations warned that melting permafrost in the Arctic is releasing significant amounts of the powerful greenhouse gas, methane. Their report estimates methane release could ultimately contribute up to 39% of all heat-trapping emissions—but had not been included in previous models of future climate.
Romm, an environmental blogger and former NOAA scientist, summarizes saying that
unprecedented rates of CO2 rise change our lives “...by making some areas
uninhabitable, increasing the number and intensity of extreme storms, creating
permanent dustbowls in many regions around the world, causing sea level to rise
2 meters by 2100. (1) (2)
(3). Other sources write about "significant extinctions of 40-70% of species assessed".
Ocean as Carbon Keeper
What does the ocean have to do with all this? As with everything oceanic, a vast amount. Not only do ocean waters slow the rate of global warming by absorbing from the atmosphere about half the CO2 that we produce by burning fossil fuels for transportation, heating and electricity production, but coastal marine ecosystems store an enormous amount of carbon in their benthic soils. (4)
salt marshes, and seagrass meadows
In recent years, scientists have uncovered in greater detail just how much carbon has been stored naturally by land and marine habitats, especially mangroves, salt marshes and seagrass meadows.
These remarkable plants pull CO2 from the air and incorporate it into their tissues in a process called "sequestration." When dead leaves and branches drop and are buried in the sediment, the carbon cannot oxidize to CO2, and is stored for very long periods of time, if not disturbed. In this way, these coastal habitats play important roles in slowing climate change and ocean acidification.
Reducing CO2 emissions is necessary to avoid serious planet-wide harm to food systems, coastlines, coastal cities, and economies, but strengthening the ability of terrestrial and marine systems to absorb CO2 and keep it out of the atmosphere for long periods of time is also essential.
hotels, and farms
Unfortunately, these same coastal areas are valuable property--wonderful locations for houses, hotels, and restaurants. When coastal habitats are destroyed or degraded, whether for this kind of development or for agriculture or aquaculture, the carbon that has been buried in the soil for centuries is suddenly exposed to air and released as the powerful heat-trapping and CO2
These formerly unsung carbon-storing ecosystems help protect us (and all life on earth) from potentially huge damage. Global warming doesn’t just raise Earth’s temperature, but also affects every temperature-sensitive process, including rainfall amounts and distribution, wind patterns, storm energy, sea-level rise and biological processes such as reproductive success, larval development rates, species distribution, disease resistance, sensitivity to toxins, among many others.
In recent years, we have lost mangrove forests for many reasons:
*to make ponds for shrimp aquaculture
*to convert marshes to farms or rice paddies
*to create river dams that prevent nourishing sediments from flowing downstream,
*to do offshore dredging, and development of coastal areas for cities or resorts
Current figures show between 150 million and 1.02 billion tons of carbon released each year from mangrove destruction--between 3 and 19 percent of the carbon released by deforestation. This results in economic damage of between $6 billion and $42 billion annually (4).
Ocean Health Index Puts Carbon Storage in the Top Ten
In the Ocean Health Index, carbon storage, is one of ten goals that reflect humankind’s most essential needs. Carbon Storage focuses on three threatened coastal habitats – seagrass meadows, salt marshes, and mangrove forests.
Although they are equivalent to less than 2% of the ocean’s surface, coastal ecosystems contribute more to long-term carbon storage and sequestration in sediments than any other ocean ecosystem. They can store large quantities of carbon for two main reasons—first, their vegetation usually grows rapidly each year, capturing (or sequestering) large amounts of carbon dioxide.
Secondly, their soils are largely anaerobic (without oxygen), so carbon that gets incorporated into the soils decomposes very slowly and can persist for hundreds or even thousands of years.
The carbon burial capacity of marine vegetated habitats is phenomenal—180 times greater than the average burial rate in the open ocean. When destroyed, these habitats rapidly release CO2 back into the atmosphere.
This Global Ocean Health Index gives carbon storage a score of “75” out of 100. The perfect score of 100 is the condition and existence of these habitats in 1980. “75” is an indication that many of these habitats have been destroyed or damaged in the past 30 years - a dangerous situation in light of the growing CO2 in our atmosphere and our need to store carbon in these habitats.
In addition to Carbon Storage, mangroves, salt marshes and sea grass beds also offer coastal protection from floods and erosion caused by storms and sea-level rise, host significant biodiversity, serve as nurseries for seafood caused by fisheries and provide opportunities for tourism and recreation.
This year, decades of warnings from scientists have also been echoed by warnings from major corporations, including Munich Re (2012) and PriceWaterhouseCoopers (2012). Both companies recently released reports on the damage that climate change is bringing. Two degrees of global warming has always been the benchmark for catastrophic changes, but PriceWaterhouseCooper’s report states that since we are not meeting the necessary goals of carbon reduction, “now one thing is clear: businesses, governments and communities across the world need to plan for a warming world – not just 2°C, but 4°C, or even 6°C.”
(1) “An Illustrated Guide to the Science of Global Warming Impacts: How We Know Inaction is the Gravest Threat Humanity Faces,” by Joe Romm, October 14, 2012. Think Progress.
Available online at:
(2) World Bank. (2012). Turn Down the Heat. A Report for the World Bank by the Potsdam Institute for Climate Impact Research and Climate Analytics. 106 pp. November 2012.
Available online at:
(3) Solomon, S., G.-K. Plattner, R. Knutti and P. Friedlingstein. (2009). Irreversible climate change due to carbon dioxide emissions. Proceedings of the National Academy of Sciences.
Available online at: http://www.pnas.org/content/early/2009/01/28/0812721106.full.pdf+html
(4) Pendleton L, Donato DC, Murray BC, Crooks S, Jenkins WA, et al. (2012). Estimating global ‘‘Blue Carbon’’ emissions from conversion and degradation of vegetated coastal ecosystems. PLoS ONE 7(9): e43542. doi:10.1371/journal.pone.0043542.