In December 2010, the carbon dioxide (CO2) level in the atmosphere reached 390 parts per million (PPM). By 2014, the CO2 level will pass 400 PPM. By the end of the 21st century, the U.S. Environmental Protection Agency projects atmospheric CO2 levels will be at least 535 PPM and possibly as high as 983 PPM. The amount of CO2 in the atmosphere is directly related to the temperature on Earth. 2010 was just ranked one of the three hottest years on record, within the hottest decade (2001-2010) on record.

Dr. Charles David Keeling developed the first accurate method for measuring the amount of carbon dioxide in the atmosphere, and in 1958 he installed a machine to measure this level at the Mauna Loa Observatory in Hawaii. For the past 52 years, the machine has hourly recorded the level of CO2 in the atmosphere. In 1958, the level was 310 PPM, and as shown in the "Keeling Curve" graph at left, it has been relentlessly climbing with the curve growing steeper: Before the Industrial Revolution, the CO2 level in the atmosphere was 280 PPM, where it had been for 1,000 years. For the past 800,000 years, the CO2 level ranged from 180 to 300 PPM – levels during which humans thrived.

The last time atmospheric CO2 was at 390 PPM was 15 to 20 million years ago – a time when the temperature was 5 to 10 degrees Fahrenheit warmer, seas were 75 to 120 feet higher, and there was no permanent ice cap in the arctic – the Earth was vastly different. Earth's history offers no comparison to the human combustion of fossil fuels. Calculating the effects of such an unprecedented, rapid rise in atmospheric CO2 is extremely complex.

Effects of global climate change (or as the current U.S. government administration prefers: "Global Climate Disruption") are already happening and include: increasing heat waves, droughts, floods, wildfires, extreme storms, forest destruction by pests, and sea level rise; the melting of Arctic sea ice, ice sheets of Greenland and Antarctica, and mountain glaciers; climate refugees; and signs of stress in coral reefs and alpine meadows – to name just a few. The extreme storms, such as heavy snows, are now occurring in areas that would not normally experience this type of weather. Northern Europe is experiencing more severe weather in winter as a result of global climate change – specifically, the jet stream is now wandering farther north and south. This change is also bringing freezing temperatures to Florida in winter. (For an explanation of the change in the jet stream path, see Judith Cohen's "Bundle Up, It's Global Warming" in the December 25th, 2010 New York Times.) Without immediate action to curb the burning of fossil fuels, deforestation, and the conversion of natural ecosystems into agricultural systems, the world faces dire effects: mass extinctions; devastating ocean acidification, brutal summer-long heat waves; rapidly rising seas; and widespread desertification. It is clear that without urgent action there will be unprecedented degradation to the ecosystems on which humans, and other wildlife, depend.

In National Audubon's 2009 report titled Birds and Climate Change: Ecological Disruption in Motion, North American Christmas Bird Count data from the past four decades was analyzed to (NYSOA Conservation Column...Continued from page 1) see if there were winter trends related to global climate change. There was a significant northward movement in 58% of the species (177 out of 305 species). There was also a movement inland from warmer coastal states. The average annual January temperature in the continental U.S. rose 5 degrees Fahrenheit over the past 40 years. The northward and inland movements "clearly point to significant ecological disruption underway, their short and long term impacts will vary for specific species and even groups." Some species may be able to adapt to the changes underway, but species that have very specialized breeding habitats will be hurt. Projected effects of climate change on high elevation habitat, used by Bicknell's Thrush, show the spruce-fir forest disappearing completely by 2100. Global climate change is suspected to be the culprit causing major changes in the extent of boreal wetlands, the chemistry of the waters, and the structure of invertebrate communities; the breeding habitat for Rusty Blackbirds. It is one of the possible causes for the staggering 95% decline in the population of Rusty Blackbirds, and declines in other species that rely on boreal wetlands.

A related milestone is approaching in 2012: the world population will reach 7 billion people (graph at right).

If this author is fortunate enough to make it to my estimated life expectancy, I will have witnessed the world population triple from 3 to 9 billion people during my lifetime. Developing countries with large populations have surging atmospheric CO2 emissions. China has just surpassed the U.S. in CO2 output, and India and Brazil are not far behind. There are billions of people who aspire to live as most Americans do: with a house, two cars, a furnace, and grocery stores filled with unlimited food options transported from around the globe.

Since the Industrial Revolution, humans have built a world dependent on burning fossil fuels. With a population nearing 7 billion, deforestation will continue, as will the conversion of natural ecosystems to agricultural lands. Humans know what we need to stop doing in order to avert catastrophe from runaway global climate change. What is needed is a model way forward – a way that is affordable. Governments of the world, and in particular, the U.S., since it was the largest contributor of CO2 to the atmosphere, need to help companies develop (affordable) alternative energy solutions so we can break our dependency on fossil fuels. We need to protect forests and other natural ecosystems from destruction and development. Major changes to the way we currently live will be needed. And, we need to find a way to curb human population growth.

Returning to the subject of birds, the National Audubon report referenced above states: "Birds are well-known barometers of environmental health. Changes in their condition can warn of threats to habitats and natural systems critical to all life on earth. Like canaries in a coal mine, they can alert us to danger. And, if we heed their warnings, caring for the birds can help us protect ourselves and the future of the world we share."