Global Warming - Have We Hit the "Tipping Point?

The frozen peat tundra of Siberia is thawing, and this will speed global warming. The peat tundra covers abbount 1 million square miles, and as it thaws tons of methane could be released into the atmosphere. Since global warming predictions have been based on known emissions of gases into the atmosphere these types of ecological changes dramatically throw off the rapidity and scale of those predictions. Sergei Kirpotin -one of the scientists who just returned from studying the peat tundra described the thaw as an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming." (See also Scientists Say Thawing Siberian Peat Bog Will Speed Up Global Warming)

This is the first melting of the peat tundra since the last ice age 11,000 years ago. The New Scientist (8/11) has the most complete explanation of what is happening in Fred Pearce's article Climate warning as Siberia melts:

"In this process [of thawing], rising air temperatures first create "frost-heave", which turns the flat permafrost into a series of hollows and hummocks known as salsas. Then as the permafrost begins to melt, water collects on the surface, forming ponds that are prevented from draining away by the frozen bog beneath. The ponds coalesce into ever larger lakes until, finally, the last permafrost melts and the lakes drain away underground."

How much, and how rapidly, the thawing of the Siberian peat bog affects global warming depends on whether or not it dries out as it thaws. If it dries, then the primary gas will be carbon dioxide. If it does not dry, then tons of methane will be released. Methane is twenty times more potent as a global warming gas than carbon dioxide. This is part of the looming threat of drilling for methane on the ocean floor - an escape of trapped methane could be globally devastating. The peat bogs of Alaska are also thawing rapidly.

These types of events - thawing tundras, melting ice caps and glaciers, warming ocean waters - are a cascading effect of global warming. They are unpredictable in terms of how much or how fast temperatures will rise. However, they are also unpredictable in terms of slowing or reversing the damage caused. The use of the term "tipping point" reflects this - the point beyond which dramatic change occurs as the cascading effects accellerate.

For most of the world's population, the image of these frozen areas are just barren stretches of earth. This is far from true. These are more than just "ecosystems." They provide a home and livlihood for indigenous peoples and for much wildlife. The destruction of these regions is more than an unimportant blip. It means the loss of peoples, of cultures, and of thousands of species that depend on these areas. This is why Indigenous Environmental Network has a special statement on Climate Justice. IEN details the effects of Indigenous peoples:

"- Indigenous Peoples, Pacific Islanders, and local land-based communities are the first to experience the devastating impacts of climate change like affects to hunting, fishing and gathering rights, land lost, food security, respiratory illness, infectious disease, and economic and cultural displacement.

- It touches on tribal sovereignty and treaty rights and is an Indigenous Nations security issue that affects the future generations to come. Climate justice is a human rights issue.

For those in the arctic region, and therfore dramatically effected by events like the tundra thawing:

"Arctic region - Those who live in the Arctic are experiencing shorter winters that disrupt the lifecycles of plants and animals that they depend on.

- The Yupik people see the winter ice pack receding sooner every year limiting walruses to breed and feed themselves.

- Rising water level from the melting glaciers forced several communities on the Arctic coast and islands to abandon their homes and traditional lands.

- Many arctic communities already have their lands and natural resources polluted by oil spills and oil development that has seriously disrupted the environment and their health."

Wallace Broecker, of Columbia University, has characterized the global warming scenarion as: "Climate is an angry beast, and we are poking it with sticks." That angry beast will lash out, and who it hits first and hardest will be indigenous peoples and those with the fewest resources to deal with it.

Posted by rowan at August 12, 2005 8:36 AM | [eMail this article!] |