Global Warming: What's it All About?
The Earth’s atmosphere is naturally composed of a number of gases that act like the glass panes of a greenhouse. Heat is retained keeping Earth's temperature stable and hospitable for life at an average temperature of 60ºF. Carbon dioxide (CO2) is the most prolific of these gases. Other contributing gases include methane (CH4), nitrous oxide (NO2), ozone (03) and halocarbons. Without the natural warming effect of these gases the average surface temperature of the Earth would be around 14ºF.
The Greenhouse Gas Phenomenon
Recently elevated concentrations of greenhouse gases in the atmosphere have had a de-stabilizing effect on the global climate, fueling the phenomenon commonly referred to as global warming. The average global surface temperature increased during the 20th century by about 1°F. According to NASA scientists, the 1990s were the warmest decade of the century, and the first decade of the 21st century is well on track to be another record-breaker. The years 2002, 2003, 2004 and 2005, along with 1998, were the warmest five years since the 1890s, with 2005 being the warmest year in over a century.
The climate and atmosphere do not react in a linear fashion to increased greenhouse gases. That is to say you cannot simply predict the specific degree of warming that each ton of carbon dioxide emitted from a power plant or a vehicle’s tailpipe will cause. The Earth’s climate has a number of feedback loops and tipping points that scientists fear will accelerate global warming beyond the rate at which it is currently occurring. For example, as CO2 emissions have increased in recent human history, the oceans have been absorbing a significant portion of these gases, but as the oceans become more CO2 concentrated, scientists anticipate they will reach a saturation point, after which each ton of anthropogenically emitted CO2 will have a more substantial impact.
Another example of this compounding effect can be found in the polar ice caps. Ice is highly reflective and acts effectively like a giant mirror, reflecting the sun’s rays back into space. As the planet warms and some of this ice melts away, a darker land or ocean surface is revealed. This darker surface tends to absorb more heat, accelerating the speed at which the planet warms with each ton of greenhouse gas emitted. As these examples illustrate, the stakes are high, and there is no time to lose in the fight against global warming.
Impacts of Global Warming
In addition to causing an increase in average global surface temperature, rising levels of greenhouse gases have a destabilizing effect on a number of different microclimates, conditions and systems. According to the Intergovernmental Panel on Climate Change, surface temperatures are on course to increase between 2.5 and 10.5ºF by the year 2100, with regions in the northern parts of North America and Asia heating by 40% above the mean increase. The increase in the temperature of the oceans is projected to accelerate the water cycle, thereby increasing the severity and rate of both storms and drought, which, along with decreased snow pack, could disrupt ecosystems, agricultural systems and water supplies.
Snow cover has decreased by 10% in the last forty years. Average sea levels have raised between 1/3 and 2/3 of a foot over the course of the 20th century and are projected to rise by at least another 1/3 of a foot and up to almost three feet by the year 2100. These coastal infringements on such a large scale could lead to not only significant environmental and ecosystem disturbances, but also major population displacement and economic upheaval.
Take Action! The City of Albany’s Climate Protection Program
In June 2006, the City of Albany committed to becoming a member of ICLEI – Local Governments for Sustainability and participating in the Alameda County Climate Protection Project (ACCPP). ACCPP was launched by ICLEI in partnership with the Alameda County Waste Management Authority & Recycling Board and the Alameda County Conference of Mayors. In committing to the project, the City embarked on an ongoing, coordinated effort to reduce the emissions that cause global warming, improve air quality, reduce waste, cut energy use and save money. Toward that end, ICLEI and the Alameda County Waste Management Authority & Recycling Board assisted the City in conducting a baseline greenhouse gas emissions inventory and set a community-wide emissions reduction target.
Baseline Greenhouse Gas Emissions Inventory
The City has developed a Climate Action Plan that consists of polices and measures that, when implemented, will enable the City to meet its target for greenhouse gas emission reductions. Several climate protection measures and policies are either in place or in the planning stages.
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