The UK-based Met Office on climate change reports that in the last ten years the planet has warmed even faster than scientists previously realized. After the year 2000, climate scientists altered their preferred method for gathering data about annual global temperatures, which may have caused them to unintentionally under-estimate the rate global warming is occurring. This makes the evidence for human-induced global warming all the more convincing. According to Dr. Vicky Pope of the Met Office, “Our analysis confirms that the signals of warming are as strong as they ever have been.”
Though planetary temperatures will always vary from one year to the next due to natural fluctuations, scientific data shows a clear global warming trend since the late 1970s. The years from 2000-2009 were the warmest decade in planetary history since record keeping began. If this trend continues the world will have to deal with impacts of global warming that are now well known to the public. These include rising sea levels, increase frequency of droughts and floods, the northward spread of tropical diseases, and the extinction of thousands of plant and animal species.
Yet while some steps have been taken to curb carbon emissions, major economies like the United States and China have yet to take the kind of sweeping action needed to prevent the worst effects of global warming. Right now the international community is meeting in Cancun, Mexico for the most important climate talks of the year. But few observers expect the meetings to produce a binding international climate treaty. This means the actions of individual countries to limit their own greenhouse emissions become all the more important.
Shortly before this month’s Met Office report was released, the UN World Meteorological Organization showed atmospheric concentrations of the two most important greenhouse gases reached record heights in 2009. Carbon dioxide concentrations now stand at 386.8 parts per million, which is a 38% increase over pre-industrial levels. Methane, the second most important greenhouse gas, has reached 1,803 parts per billion, a 158% increase since before the Industrial Revolution.
Climate experts like NASA scientist James Hansen have warned that to preserve the planet in a state friendly to human civilization, atmospheric carbon dioxide concentrations must be brought down to 350 parts per million. According to Hansen, “That will be a hard task, but not impossible. We need to stop taking carbon out of the ground and putting it into the air.”
This means major economies around the world need to dramatically cut back on their reliance on fossil fuels for energy. China and the United States, as the biggest and second-biggest greenhouse gas emitters, play an especially important roll in this process. Yet while China has become a major polluter relatively recently, the US has a long history of reliance on fossil fuels, and the economic means to shift to renewable energy sources more easily. It therefore seems likely that for China and other developing countries to agree to limit their greenhouse emissions, the United States must take the first step.
Earlier this year the US Senate failed to pass a national energy and climate bill, casting national efforts to curb global warming into doubt. However the US Environmental Protection Agency has worked with the Department of Transportation on a plan to improve the fuel efficiency of US vehicles for the first time in over a decade. Meanwhile California and several other states have ambitious plans to reduce their carbon footprints and transition to cleaner energy sources. Such initiatives show curbing carbon emissions is a realistic goal, and that it can be accomplished while creating new jobs in the renewable energy industries.
International authorities like the Met Office and the World Meteorological Organization have made the consequence of not curbing emissions and fossil fuel consumption quite clear, and serve to reinforce the scientific evidence for global warming. Now the US and other countries must try to replicate successful efforts which have reduced emissions at the local and regional levels. If world leaders act quickly enough, there will still be time to avert the most catastrophic consequences of global warming.