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Old Tuesday, November 24, 2009
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Earth's Protection Shield is Being Destroyed - Ozone Depletion and Global Warming

Stratospheric Ozone
The Earth's atmosphere is made up of different layers. The layer closest to the surface is called the troposphere which extends from the Earth's surface up to about 10 kilometers. The ozone layer is located above the troposphere in the stratosphere (10 km to about 50 km high). Stratospheric ozone is Earth's natural protection for all life forms, shielding our planet from harmful ultraviolet-B (UV-B) radiation. UV-B radiation is harmful to humans, animals, and plant life. The ozone layer is being destroyed by certain industrial chemicals including ozone depleting refrigerants, halons, and methyl bromide, a deadly pesticide used on crops.

Colder Temperatures Increase Ozone Damage
Ozone depletion damage gets much worse when the stratosphere is very cold. This has been the case the past two years, causing extensive ozone depletion. This past winter, ozone depletion reached the most severe levels ever recorded over the Northern Hemisphere. Western United States ozone levels also continue to drop 3-4 percent per decade. Even if all of our efforts to stop harmful emissions are successful, the ozone layer is not expected to begin recovery until around 2020 at the earliest.
Montreal Protocol
Under the auspices of United Nations Environment Programme (UNEP), Governments of the world, including the United States have cooperatively taken action to stop ozone depletion with the "The Montreal Protocol on Substances that Deplete the Ozone Layer", signed in 1987.
Global Warming

The terms, global warming and climate change are often used interchangeably. Gases such as carbon dioxide, methane, nitrous oxide, and refrigerants create a greenhouse effect by trapping heat in the lower atmosphere. This makes the Earth warmer because the sun's rays are allowed into the lower atmosphere but the heat from these rays isn't able to escape.

Global Warming has been Verified
In 1995, 2,500 scientists prepared a report called the Second Assessment of the Intergovernmental Panel on Climate Change (IPCC). The IPCC reports that global warming and climate change is a reality, and that human emissions of greenhouse cases are a culprit. There are several harmful impacts that result from a global warming trend. Impacts from global warming include sea level rise, more extreme weather events including heat waves, frosts, droughts, storms, extinction of species, loss of entire forests, marine life destructionand glacial retreat.
Earth's Temperature is Rising
1998 was the hottest year since accurate records began in the 1840s, and 10 of the hottest years have occurred during the last 15 years. By examining growth rings from trees and ice cores drilled in Antarctica, scientists have determined that the past decade was the warmest in more than four centuries, and that the current rate of warming is probably unprecedented in at least 10,000 years.

The damage to our environment has already started. For example, sea level has risen from 10-25 centimeters and will continue to rise for centuries even if we stop all global warming emissions immediately. As the world warms, the outlook for all life forms looks bleak, unless we can turn down the heat by reducing concentrations of greenhouse gases in the atmosphere.
Kyoto Protocol
The United Nations has developed a framework the "Kyoto Protocol on Climate Change", signed in 1997 convention on global warming and climate change. The adoption of the Kyoto protocol strengthens the framework with new policies and measures including quantified limitation and reduction objectives to greenhouse gas emissions not covered by the Montreal Protocol.
Global Warming Can Increase Ozone Depletion
Scientist's are concerned that continued global warming will accelerate ozone destruction and increase stratospheric ozone depletion. Ozone depletion gets worse when the stratosphere (where the ozone layer is), becomes colder. Because global warming traps heat in the troposphere, less heat reaches the stratosphere which will make it colder. Greenhouse gases act like a blanket for the troposphere and make the stratosphere colder. In other words, global warming can make ozone depletion much worse right when it is supposed to begin its recovery during the next century.
Effects of Ozone Depletion and Global Warming
(UV-B) radiation causes skin cancer, cataracts and immune suppression in both animals and humans. UV-B also damages plants including hardwood forests, and phytoplankton (an alga is a type of phytoplankton which is the building block of the oceanic food chain).
Effect on Infectious Diseases
Most infectious diseases are transmitted by insects and rodents. Transmitters of disease are called vectors. For example, mosquitoes transmit malaria, dengue and viral encephalitis (inflammation of the brain). Like other animals and plants, vectors are accustomed to certain climate conditions. If the climate becomes warmer, the mosquito will try to fly to new places where it can survive and expose more people to the disease. Changes in sea surface temperature and sea level can lead to higher incidence of water-borne infectious and toxin-related illnesses such as malaria (severe chills and fever), cholera (intestinal disease), dengue (characterized by severe pains in the joints and back), and leishmaniasis (skin ulcers).
Human susceptibility to infections can be further compounded by malnutrition. UV-B radiation from ozone depletion damages both plants and animals. UV-B harms amphibian eggs, midge larvae and trout. Crops that are damaged will reduce food availability. UV-B also can damage mammalian immune systems which makes humans and other animals more susceptible to infectious diseases.
Approximately 92 million people are expected to become refugees from global warming and climate change by 2100, not including any added from population growth.
Effects on Earth's Food Chain
Ozone depletion and global warming have harmful effects on plants and animals. If allowed to continue, our food chain will be seriously disrupted. For example, phytoplantkton are tiny floating algae in the ocean which are the base of the marine food chain. In Antarctica, there has been upwards of 50 percent ozone depletion. This means that an unusually high amount of UV-B radiation has reached the Earth's surface in the Antarctic region. UV-B harms the productivity of phytoplankton, thereby reducing the available food for animals that feed on phytoplankton. Krill eat phytoplankton and penguins eat krill. From a climate change perspective, phytoplankton normally absorb a lot of carbon from the air. As phytoplankton dies from UV-B radiation, this carbon is no longer absorbed. This means that more carbon will be left in the atmosphere, contributing to more global warming. More global warming can increase ozone depletion, which kills more phytoplankton, and the process repeats itself.
"Total Environmental Impact" of Refrigerants
Six parameters define the "total environmental impact" of refrigerants on our environment.
  • Ozone Depletion Potential (ODP)
  • Global Warming Potential (GWP)
  • Atmospheric Life
  • Energy Use
  • Equipment Emission Rate
  • Refrigerant Charge

Approximately 70 percent of the world's electricity is generated by the burning of fossil fuels. For every additional kWh used, there are more greenhouse gas emissions generated by electric utility power plants. This is the indirect effect of global warming refrigerants. The environmental impact of even small changes in chiller energy use has an impact. There is a need to use refrigerants that minimize both ODP and GWP to address global environmental concerns. If the efficiency of every centrifugal chiller in the world were increased by only 0.08 kW/ton, power plant-generated greenhouse gas emissions would be reduced by literally billions of pounds. This is an amount equal to removing nearly two million cars from the road each year, or to planting nearly a half billion trees every year.
Action Plan For Organizations Using Refrigerants
Most refrigerants used in air conditioning and refrigeration contribute to global warming in addition to ozone depletion. Even the new non-ozone depleting alternative refrigerants add to the global warming problem. Businesses and organizations using refrigerants are encouraged to take action now to do what's right for both their organization and for the environment. Persons responsible for HVAC and/or environmental concerns in their company or organization need to take strong, immediate actions to reduce ozone depletion and global warming.
Minimize emissions of ozone depleting (ODP) and direct global warming (GWP) refrigerants used by your organization. The most effective way to start reducing emissions is to implement a Refrigerant Management Plan and insure that your organization is complying with EPA's Section 608 Refrigerant Recycling Regulations. Refrigerants should be handled as a controlled substance. A defined leak management program, including leak monitoring and leak repair policies is essential. Provide Refrigerant Management and Regulations Compliance Training to your responsible employees. Organization's using refrigerants should review and implement industry best practices in refrigerant management to minimize emissions at every stage of refrigerant handling. Implement a process to keep current with regulatory changes to insure going compliance requirements are met.
Reduce energy consumption of HVAC systems using refrigerants to reduce indirect global warming emissions. Conduct a building tune-up to reduce your heating, cooling, and electrical loads, and thus your overall energy consumption.
Replace older HVAC systems containing high ozone depleting and/or global warming refrigerants with newer, more efficient systems. Frequently, HVAC systems are oversized. Thus, you may want to consider right-sizing your existing system with a smaller, more energy-efficient one that matches the newly reduced loads. The operating costs of a high efficiency system may offer an attractive pay back of your investment. Evaluate HVAC systems on a total cost of ownership basis, rather than first cost.

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