Global warming is an average increase in the earth’s overall temperature. Increased temperatures affect climate and human dependence on earth’s resources. The enormous increase in
greenhouse gasses (GHGs) since the beginning of the industrial age is believed to be the causation of increasing global warming. Without a global effort to quickly reverse the trend, the potential for food shortages, wars over water, and displaced habitats is, unfortunately, not only possible, but likely.
Current_State_of_Affairs
FAQs
How_do_GHGs_affect_temperature?
Is_Global_Warming_natural_or_Man-Made?
Do_we_need_to_save_the_planet?
Do_scientists_agree_that_global_warming_is_certain?
Predictions
Sea_Levels_&_Wetlands
Water
Abrupt_climate_change
What_is_being_done
What_could_be_done
What_you_can_do
Temperatures
The earth’s average surface temperature has increased about 1°F in the last 100 years per the Intergovernmental Panel on Climate Change (IPCC). The IPCC is a group of scientists formed by the U.N. to evaluate risk of climate change based on peer reviewed and scientific journals. They explain these temperature trends:
- Daily maximum and minimum temperatures have increased, with minimum temperatures increasing at a faster rate than maximum temperatures.
- Land areas have warmed faster than ocean areas.
- Winter months have warmed faster than summer months.
- The number of days below freezing decreased from 1950 to 1999 in the United States and most land areas of the Northern Hemisphere and Southern Hemisphere.
- Average temperatures in the Arctic have increased at almost twice the global rate in the past 100 years.
Scientists depend on temperature records only from the last century. Other indications, though not direct temperature observations, help scientists understand current weather patterns include:
- Historical documents such as medieval diaries and ancient weather records
- Tree rings: ring width shows variations in temperature and precipitation.
- Ice cores: trapped air bubbles in pieces of ice sheets in Antarctica and Greenland show climate shifting.
Greenhouse gases
Some GHG sources are natural (See Natural vs. Man-made FAQ below), but the four rising greenhouse gases (GHGs) from human activities include:
- Carbon Dioxide (CO2) Burning fossil fuels, solid waste, & wood. Chemical reactions like manufacturing cement
- Methane (CH4) Coal, natural gas, and oil production & transportation. Livestock & agricultural practices. Decay of waste in landfills
- Nitrous Oxide (N2O) Agricultural & Industrial processes. Burning fossil fuels & solid waste (310 times more damaging than CO2)
- Fluorinated Gases Synthetics used in place of banned ozone depleting chemicals
Carbon Dioxide
Carbon dioxide (CO2) is the greatest greenhouse gas in quantity whose main source is from burning fossil fuels for transportation or electricity production. Global atmospheric concentrations of CO2 were 35% higher in 2005 than before the Industrial Revolution. The greatest increase began during the 1940s.
Precipitation
Rising temperatures increase evaporation, which causes more precipitation. The IPCC is not certain about human influences, yet reports the following trends:
* Increased precipitation over land north of 30 degrees from 1900-2005.
* Decreased precipitation over land in the tropics.
* North & South America, northern Europe, and central Asia have become wetter.
* The Sahel, the Mediterranean, southern Africa, and parts of southern Asia have become drier.
* Mid and high latitude oceans may have had increased precipitation.
* Low latitude oceans may have had less precipitation.
* There has been no significant global precipitation trend.
* The number of heavy precipitation events have increased over the last century.
* Droughts have increased since the 1970s.
* There is no long-term evidence of systematic storm changes over the last 100 years.
Plants and Animals
As temperatures shift, ecosystems shift with them. The shift may benefit species by increasing their range. However, the shift may harm endangered species, especially if they are limited by available habitat, low populations, or narrow temperature tolerances. Regional climate change has already caused:
- Plant and animal shifts to the north and to higher elevations
- Changes in growth seasons and stages such as spring time events
- Migration patterns
An impact of global warming on sea creatures has increased Dead Zones in the oceans. When tiny, ocean plants called phytoplankton die then decompose, bacteria increases and oxygen decreases. These oxygen depleted areas are called Dead Zones because marine creatures cannot survive in them. Growing temperatures increase wind strengths, which help to upwell nutrients in ocean currents. An abundance of nutrients increases phytoplankton growth, resulting in waters without enepleted of oxygen. Dead zones are multiplying on the west coast of the U.S., as well as in the Benguela Current of South Africa.
As animals change their migratory patterns in search of food due to loss of wetlands and grasses, species are appearing in new places and quickly disappearing from their usual areas. Trout and salmon have migrated to follow their food supplies that have moved to remain in cool waters. The Red Fox, a native to North America and Europe is migrating to the Arctic. Since many species can not migrate fast enough, they are endangered of becoming extinct.
Health
Scientist predict that diseases found in tropical, low latitude regions will move north with increasing temperatures. A disease called Chikungunya has already moved north of its range. Carried by the tiger mosquito, the disease traveled from the Indian Ocean region to Italy last year. Dr. Roberto Bertollini, from the World Health Organization said this is the first tropical disease epidemic in a developed, European country. He claimed that climate change creates living conditions for the mosquito and for diseases that didn’t exist there previously.
Glaciers & Coasts
Over 2 billion people live within 100km of the coast. Sea levels rise when ice caps melt. Over the Arctic Ocean, about four feet of glaciers have melted. Year round arctic sea ice has declined by 14% from 1978 to 1998. In 2006, Greenland lost 52 cubic miles of ice. As glaciers melt, the process speeds up. Ice reflects solar heat, so when ice cover decreases, more rocks are exposed. Rocks hold heat, which helps to melt ice.
Average sea level rise was 4.8 to 8.8 inches in the last century, though actual levels may not have been well documented. Factors other than global warming cause sea level fluctuations and sea level has dropped in some regions. Antarctica has seen warming and cooling over the last 30 years. Though some ice has melted, satellites show no significant change in sea ice since 1973.
How do GHGs affect temperature?
Is Global Warming natural or Man-Made?
Do we need to save the planet?
Do scientists agree that global warming is certain?
How do GHGs affect temperature?
The earth absorbs and reflects the sun’s radiation. GHGs prevent reflecting radiation from leaving the earth’s atmosphere. GHGs are vital for keeping temperatures warm enough to sustain life on earth, but their increase raises temperatures, which affect precipitation, barometric pressure, and wind conditions.
Is Global Warming natural or Man-Made?
Scientists may not agree about how much warming will occur and at what rate, but almost all agree that the earth's temperature is on the rise. Some believe that it is a natural cycle. However, most do not.
A very small part of the scientific community is uncertain about the affect of natural causes vs. man-made causes. Scientists are studying the following to better predict outcomes of causes:
- Natural climatic variations
- Changes in the sun's energy
- Land-use changes
- Warming or cooling effects of pollutant aerosols
- Impacts of changing humidity and cloud cover.
- Future greenhouse emissions projections
- The climate system’s response within a narrow range.
- Rapid or abrupt climate change (See Abrupt Climate Change below)
Scientist recognize two natural climate change eras. One warming in Europe, Greenland, and Asia, called the Medieval Climate Anomaly, may have occurred from about 900 to 1300 AD. Another event, called The Little Ice Age, was a global cooling event between about 1500 and 1850 in which average temperatures were about 2°F cooler than today’s.
In addition, GHG inventories only include human related sources, even though natural processes emit GHGs. Primary CO2 emissions from natural sources include:
- Animal and plant respiration
- Ocean’s surface absorption and release of CO2
- Volcanic eruptions (which also release cooling gases)
Natural sources in the chart below account for about 40% of methane emissions. Bacteria in wetlands produce methane when decomposing organic matter. Termites and ocean creatures produce methane in their digestion. Methane is also released in ocean sediments and hydrates, compounds of solids and water molecules containing methane. Microbial processes in soils and oceans also produce nitrous oxide, a GHG.
Source: EPA
Do we need to save the planet?
Some people believe global environmental systems are bigger than humans and that the effect of our actions are overrated. The overwhelming scientific consensus, however, is that human disregard to our environment is creating conditions that may put our species at risk. No matter what happens, the planet is not in danger. We are. The planet has seen extreme temperatures and species come and go. A more apt slogan to "Save the Planet" is "We need to save ourselves".
Do scientists agree that global warming is certain?
Controversy & Scientific Uncertainty. Scientists across the board do agree that CO2 is increasing in the atmosphere. They also agree that global temperatures are increasing. The biggest controversy and scientific uncertainty is the projected impact of CO2 emissions on increased temperatures. However, not all scientists agree on the specifics of global climate change. According to the Science and Environmental Policy Project (SEPP) temperatures have increased over the last few years, but not appreciably over the last 50 years. SEPP is a group of scientists who are not convinced that human activity is the leading cause of recent global warming. SEPP scientists conclude that models leave out important factors such as ocean currents, dust, and clouds. SEPP has received funding from major oil corporations.
Predictions
Scientists at the Oak Ridge National Laboratory in the U.S. predict the following results due to increasing temperatures:
Increasing GHGs
The IPCC predicts that total GHGs will continue to increase, with developing countries becoming the main polluters, due to their growing industrialization. They also predict that China, Brazil, India, and the U.S. will have the greatest increase in non-CO2 GHGs by 2020. As these countries increase their domestic output, there is more demand for energy, and people have more disposable income and quickly trade their bicycles for automobiles.
Source: EPA
Crops
If temperatures continue to increase, parts of the U.S. will become too hot and dry to grow wheat. It is believed that by 2020 the Napa Valley in California will be too hot to sustain wine vineyards. Alaska and Canada may be able to farm wheat as far as two degrees from the Arctic Circle. One study showed that the wheat farming region of India, the second most populated country in the world, will shrink by 50%. Agricultural researchers are working on better techniques, such as using less nitrogen fertilizer, a source of nitrous oxide.
Forests
Climate change may alter forest habitat, depending on pollution, forest management, and land-use change. The IPCC predicts the following changes for North America’s forests:
- Climate change may cause 10-20% forest growth over the next century. However, extreme and/or long-term climate change may cause widespread forest decline.
- Wildfires and insect outbreaks may intensify in a warmer climate with drier soils and longer growing seasons.
- Long-term effects of fire depend heavily on human fire management.
Sea Levels & Wetlands
The IPCC predicts average global sea levels to rise by .6 to 2 feet in the next century. (Average sea level rise was 4.8 to 8.8 inches in the last century). As sea level rises, new wetlands will form. However, new wetlands may form at a slower rate than sea level rises, especially on developed coasts. The IPCC predicts an upper limit of 33% coastal wetland loss by 2080. This loss would affect more than 2 billion people living within 100 km of the coast.
Water
Scientists predict that global climate change will affect future water availability in the following ways :
- Changes in precipitation patterns may increase drought.
- Temperature increases will lead to more rain than snow.
- Temperature increases will lead to a shorter season of snow pack (a natural reservoir of fresh water).
- Flooding will increase in the winter, decreasing river flows in spring and summer.
- Sea level rise will decrease fresh water supplies for coastal regions.
Abrupt climate change
Abrupt climate change refers to widespread, large scale changes in earth’s climate system occurring over a short time (within a few decades). Some scientists predict drastic changes in warming or cooling, precipitation, ice shelves, and sea level could be triggered by:
- Changes in the Earth’s orbit
- Brightening or dimming of the sun
- Melting or surging ice sheets
- Strengthening or weakening of ocean currents (as dramatized in the movie "The Day After")
- Emissions of gases and particles into the atmosphere
Human actions can affect these triggers, but due to the limits of models and past climate changes,“future abrupt changes cannot be predicted with confidence, and climate surprises are to be expected,” says the National Research Council.
Change in the Gulf Stream is one possible trigger. The Gulf Stream carries warm water from the Gulf of Mexico past the Eastern U.S. to Canada’s Atlantic coast, warming the U.S. and Europe by 41°F. The worst impact of global climate change on ocean currents would be to trigger a new ice age all over Europe by sending cold waters into the ocean from melting northern ice fields. The least impact of global climate change on ocean currents would be minor winter temperature drops in North America’s east coast and northwestern Europe.
Scientific models and theories for such instability are limited. Some researchers say that these triggers depend on one another and drastic changes would require multiple triggers. Research, including ice core samples, shows that earth’s climate is relatively stable and slow in changing.
In 1992, the Rio Earth Summit created several treaties and directional goals to confront the growing problems of global warming, species extinction and the lack of farmable land to feed the populations of poor countries. Unfortunately, there has been little concrete result in the years that followed. The most significant effort to combat global warming to date has been the Kyoto Protocol.
Kyoto Protocol
The Kyoto Protocol is an emissions limit under the United Nations Framework Convention on Climate Change, an international treaty to reduce GHGs. 174 countries have ratified the Kyoto Protocol (conspicuously absent is the United States). Developing country participants must monitor and report emissions while developed countries reduce total emissions. Wealthier developed countries must also promote and facilitate climate friendly technologies for developing countries. The Convention’s compliance committee uses a national registry database for report and review of participating countries. Participating countries operate with:
- Clean development. Developing countries can earn and sell emission reduction units with lower emission projects.
- Emissions trading. Countries can buy and sell emission credits and use them to meet emission goals.
- Joint implementation. Developed countries invest in reduced emissions projects in developing countries in place of reducing emissions in their own country.
About four months after the Kyoto Protocol (December, 1997), more than 15,000 scientists signed a petition in response, urging the U.S. government to reject the protocol. The IPCC, who made the report supporting the Protocol, had less than 2,000 members, and only a fraction of climate scientists. Some scientists on the panel were critical of the report submitted for the Protocol and signed the petition as well.
Green Power
Energy alternatives of burning fossil fuels reduce human influences the most. Over 50 countries in the world have set renewable energy goals, including the EU, 13 developing countries, and many states or provinces in the U.S. and Canada. 2006 growth rates were in the double digits:
Wind 25-30%
Solar PV 50-60%
Solar Thermal 15-20%
Biofuels 15-20%
Brazil’s biofuels program has saved the country $100 billion in debt. In 2007, China issued a global warming strategy that included renewable energies along with reforestation and energy efficiency.
Sustainable programs are popping up in response to climate change. Cities worldwide are taking steps to use renewable energy, increase energy efficient buildings, and reduce air pollution, including GHGs. One example is Cool Cities in the U.S., an initiative for residents and local city leaders. Over 950 cities have committed to the goal of reducing global warming.
Carbon Reduction
Scientists say we have the technology to reduce global warming. Some of the major areas of improvement to reduce dependence on oil and fossil fuels include:
- Invest in renewable energy and energy efficiency: Wind, solar, geothermal, and biofuel energies
- Increase car efficiencies: reduce emissions from cars and trucks
The IPCC claims that the world must reduce emissions by 50% of 1990 levels by 2050 in order to prevent a temperature increase of over two degrees. However, a study by the Union of Concerned Scientists (UCS), a science based, environmental non-profit , shows that some nations may need to reduce emissions much more. For example, they claim that the U.S. would need to reduce emissions by 78% of 1990 levels by 2050 to avoid a 2 degree temperature rise.
The UCS suggests a mandatory carbon credit trading program to reduce emissions. Governments should put a limit on emissions and issue credits, or emission allowances, to meet that limit. Trading would operate in an economic market in which polluters could purchase credits from others who have reduced their emissions. The UCS explains the following as essential for a successful carbon market:
- Strict emission limits and goals for the future
- All pollution emitters included
- All GHGs included
- Auction credits instead of giving them away
- Invest auction revenues in renewable energy and energy efficiencies
- Let the market run on it’s own; don’t set a maximum price on credits
- Cooperate with other countries, but allow trading only from countries with emission limits
Other actions that should occur:
- Fuel cells automobile development
- Green construction
- Increased energy efficiency
- Ceasing deforestation
- Move from fossil-fuel based power production to renewable power.
See 
Buying Green Power
Carbon Sequestration
It is predicted that even if we did not add any more CO2 in to the air, the average global temperature will still rise by .5 degrees centigrade. Research is being done to analyze the feasibility of technology (high tech and low tech) that removes CO2 from the atmosphere so we can not only stop the damage, but also reverse the damage already done. The methods listed have not yet proved that they can be effective. These include:
- Capturing CO2 and neutralizing it at the source on emission stacks for power plants, cement companies, and refineries through a chemical process.
- Capture CO2 and pump it into underground caverns, abandoned oil wells or below the ocean floor.
- Creating microbes that consume COs and excrete less harmful waste.
- Increasing plankton yields by adding iron oxides (rust dust) to the ocean.
- Consider a more fuel-efficient car or hybrid for your next purchase. With each gallon of gas you burn, 20 pounds of CO2 are released into the air.
- Use your less fuel-efficient vehicle only when carpooling.
- Keep tires well inflated, accelerate and brake smoothly
- Drive less overall, and take public transit when possible
- Buy your electricity from a utility that uses renewable energy
- Buy energy saving appliances & use less energy overall
- Unplug unused appliances, such as the extra freezer in the garage
- Do a home energy audit
- Buy sustainable harvested timber
Human related non-CO2 sources include agriculture, livestock, landfills, and wastewater treatment. Be conservative with water use and meat consumption, especially beef. Recycle, compost, and generate less waste. Check your Carbon Footprint and make strides to steadily reduce it.
