|
|
|
For the last 800,000 years, until 1970, this planet’s carbon dioxide (CO2) levels remained within the generally recognized “safe” range of 180-300 parts per million (ppm). However, CO2 levels started to exceed that range about three decades ago. And, we continue to add about 2 ppm to the atmosphere each year. That may not sound like much, but consider this: in the one million years prior to modern times (i.e. “The Industrial Age”), the fastest increase of CO2 was 30 ppm over a 1000-year period. Recently, however, humans have increased atmospheric CO2 levels by 30 ppm in just 17 years, and CO2 levels are currently at 383 ppm (Amos, 2007). We are in uncharted waters.
Carbon dioxide is the most important greenhouse gas in our atmosphere. The primary source of increased CO2 levels is from the burning of fossil fuels (IPCC 2007). Carbon dioxide, as well as other greenhouse gases, have warmed the planet significantly – 0.8°F to be exact – since pre-industrial times, and here are some of the very observable changes:
- The polar ice cap is now melting at the alarming rate of nine percent per decade. Arctic ice cover has decreased 23 percent over the past two winters (NASA, 2007).
- Greenland and Antarctica are each losing ice mass at a rate of about 150 cubic kilometers per year. These figures represent more than a doubling of rates from just a few years earlier (Casenave, 2006).
- Mountain glacier and snow coverage has, on average, declined in both hemispheres. Widespread decreases in glaciers and ice caps, in addition to thermal expansion, have contributed to sea level rise of over 6 inches since 1900 (IPCC,2007). Even just half a foot of sea level rise has been enough to increase salinity of bays and rivers, threaten groundwater tables, and intensify flooding. The IPCC has concluded that the impacts of future sea level rise are “virtually certain to be overwhelmingly negative” (IPCC, 2007).
- Since 1850, 123 out of 150 glaciers in Glacier National Park have melted completely. The remaining 27 are forecasted to disappear by 2030 (Fagre, 2003).
- Western North America’s wildfire season has more than doubled in length (Running, 2007). The 2006 wildfire season set new records, both in terms of the number of reported fires as well as acres burned. Close to 100,000 fires were reported and nearly 10 million acres burned, 125 percent above the 10-year average.
- Drought has increased across the Mediterranean, Southern Africa, and Southern Asia (IPCC, 2007).
- Plant and animal ranges have shifted toward the poles and higher elevations, and the timing of many life-cycle events, such as blooming, migration and insect emergence, has shifted to earlier in the spring and later in the autumn (IPCC, 2007b).
- The ten warmest years since 1850 have all occurred since 1995 (IPCC, 2007).
|
These are just a few examples of what has happened with an increase of only 0.8°F of warming. But here’s the kicker: the Earth’s temperature will still rise another 0.6°F even if we completely stopped burning fossil fuels tomorrow. (This happens because of what scientists call “thermal inertia”, meaning that the Earth is so big that its systems take a long time to “get revved up” – and, just as importantly, to slow down.) These temperature increases mean that the changes we have seen will become more intense, and we will see new changes occurring (IPCC, 2007).
Now consider these additional thoughts:
Chances are good that we will not stop burning fossil fuels tomorrow. More CO2 will be emitted to the atmosphere as we continue to satisfy our energy needs, and temperatures will rise even longer than we continue to emit CO2.
Intergovernmental Panel on Climate Change (IPCC) reports (often cited on this page) are conservative – by design. Their reports represent the views of thousands of scientists and are produced as a consensus among nations, resulting in authoritative and widely accepted conclusions. However, IPCC reports cannot take into account the most recently available science. Take for example, this IPCC statement: “late-summer [Arctic] sea-ice is expected to disappear almost completely toward the end of the 21st century.” In the year since the latest IPCC report was released, Arctic sea ice has shrunk twenty percent, and “retreat is larger than in any of the 19 IPCC models”. These latest findings reveal that climate change is happening even faster than the IPCC predicts (Furevik, 2005).
It is imperative that we, as individuals, families, communities, states, corporations, and nations, become aware of the urgency of this crisis and the risk involved in continuing to emit greenhouse gases. We must join together to act quickly and decisively to bring about a rapid reduction in greenhouse gas emissions.
For if we do not significantly cut CO2 emissions soon, additional warming will dramatically alter the planet as we know it, and here’s how:
In North America alone, we can expect that:
- Crop yields will decrease, which means higher food prices.
- Heat waves become more frequent, hotter, and last longer.
- Snow-pack in the western mountains continues to decrease- which means fewer days for winter snow sports.
- More flooding in winter and less water in summer- in places that already compete for scarce water resources.
- More intense storms and rising sea levels will threaten coastal cities with increased flooding and greater economic losses.
|
Around the world we can expect that:
- 150 million people living at or near sea level will become the world’s first mass wave of environmental refugees.
- The North Pole will be ice-free in summer by 2030, and 2/3rds of all polar bears will be extinct.
- Parts of Africa will face severe drought, a 50% drop in crop yield, resulting in food shortages and famine by 2020.
- Freshwater availability to diminish in parts of Asia and South America, where as many as 1 billion people rely on glacial melt for drinking water.
- Air quality in cities world-wide will decline as temperatures rise.
- Mountains of Europe will have less snow, which means less tourism and great economic loss.
- Coral reefs in Australia and around the world will bleach- threatening the marine ecosystem, the fishing industry, and fish as a food source.
- Food scarcity will incite competition and conflict.
|
But only with a well-planned, multi-pronged approach.
We must raise awareness of the climate crisis.
We must put pressure on Congress to pass meaningful climate change legislation.
We must switch to renewable energy.
We must increase energy efficiency.
We must transition to a clean, green energy economy.
You can be a part of the solution in many ways. And one of them is by joining us at Climate Ride 2008. Please register or make a donation today!
References
IPCC 2007: http://www.ipcc-wg2.org/index.html
IPCC 2007b: http://www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter1.pdf
Amos, 2007: http://news.bbc.co.uk/2/hi/science/nature/5314592.stm
NASA, 2007: http://www.jpl.nasa.gov/news/news.cfm?release=2007-112
Casenave 2006: How fast are the ice sheets melting? Science 314 1250-2
Fagre, 2003: http://www.nrmsc.usgs.gov/products/GCC/Bioscience_Hall_03.pdf
Running, 2007: Five stages of climate grief, on DVD.
Furevik, 2005: http://www.norway.org/NR/rdonlyres/3F179CEC-67E4-4512-8229-
701B48B5E54E/36279/fureviktore1.pdf
http://www.carbonequity.info/images/seaice07.jpg
|
|
|
|
|
|
|
|
