Storm Warnings Intensify
The time to stop global warming is now. The health of our planet lies in the balance.
The world's leaders meet at the end of 2009 in Copenhagen to determine the fate of the climate. They could set us on the path to a deep emissions cuts or they could lock the planet into catastrophic, irreversible climate change.
Climate change is a reality. Today, our world is hotter than it has been in two thousand years. By the end of the century, if current trends continue, the global temperature will likely climb higher than at any time in the past two million years. While the end of the 20th century may not necessarily be the warmest time in Earth's history, what is unique is that the warmth is global and cannot be explained by the natural mechanisms that explain previous warm periods. There is a broad scientific consensus that humanity is in large part responsible for this change, and that choices we make today will decide the climate of the future.
There is, in fact, a broad and overwhelming scientific consensus that climate change is occurring, is caused in large part by human activities (such as burning fossil fuels), and if left un-checked will likely have disastrous consequences.
The primary human source of carbon dioxide (CO2) in the atmosphere is from the burning of fossil fuels for energy production and transport. Changes in land use and deforestation also contribute significantly. Trees, for example, are natural 'carbon sinks' - they absorb carbon dioxide while alive and when they are destroyed, carbon dioxide is released into the atmosphere. Once in the atmosphere, most of the carbon dioxide stays there for 50 to 200 years, and some of it stays there indefinitely.
No one knows how much warming is "safe". What we do know is that climate change is already harming people and ecosystems. Its reality can be seen in melting glaciers, disintegrating polar ice, thawing permafrost, dying coral reefs, rising sea levels, changing ecosystems and fatal heat waves. And it is not only scientists that are witnessing these changes. From Inuit in the far north to islanders near the equator - people are already struggling with the impacts of climate change.
There is strong evidence that extreme weather events – such as hurricanes, floods, droughts and heat waves – are increasing because of climate change. In fact, the Financial Initiative of the UN Environment Programme (UNEP) recently calculated that the economic costs of global warming are doubling every decade. The cumulative number of people affected by disasters rose to two billion in the 1990s, up from 740 million in the 1970s. Virtually all of these millions were concentrated in poorer countries.
MIT isn't the only one noticing how ferocious hurricanes have become. Hear from ordinary people whose lives have been affected by hurricanes.
