Global Warming Effect

Ice Under Fire: Antarctica

The disintegrating face of the Müller Ice Shelf, Lallemand Fjord, Antarctic Peninsula, 67° South, April 2, 1999. This small shelf, fed by glaciers from the Loubet Coast, has been receding recently after growing over a 400-year cooling period. Like other receding ice shelves such as the larger Larsen, it may be a sensitive monitor of rising regional temperatures. The Larsen Ice Shelf lost a 1200 square mile section early in 2002. Earlier in the 1990's other huge sections of this shelf disintegrated. In 2003 Argentine glaciologists reported that the land-based glaciers exposed by the removal of those sections had surged rapidly into the ocean. Thus, although ice shelves are floating and do not add to sea level when they melt or break up, land based glaciers released by such events definitely will add to sea level.

Another view of the Müller Ice Shelf calving rapidly (right). Across the Peninsula, seven monitored ice shelves have declined by a total of about 13,500 km² since 1974, according to the National Snow and Ice Data Center. This is nearly the area of Connectcut. On the Larsen shelf (satellite view left), about 3,250 km² of shelf in area B disintegrated in a 35-day period beginning on 31 January 2002. Eugene Domack, Hamilton College geologist, and others believe this portion of the shelf may have been stable for about 12,000 years before this year's collapse.



Technicians for the National Science Foundation on the rear deck of the research vessel, Nathaniel B. Palmer, prepare a kasten core device to lower into sediment near the Müller Ice Shelf. This is during a study by Dr. Eugene Domack, funded by the National Science Foundation, on the history of climate in peninsular Antarctica. All ice shelves in the area have been receding, but because they were already floating they do not raise sea level. The concern is that landed glaciers behind the shelves may be next to begin rapid retreat, which would raise ocean levels.

This mile-long ice cliff of Marr Ice Piedmont, Anvers Island, has receded about 500 meters since the mid 1960s. The cliff's previous position was to the left of the line of ice floating in the harbor and extended to the headland at the extreme upper left. The regional temperature has increased 5° C in winter over the past 50 years. This reduces seasonal icepack, disrupts growth of krill and changes conditions on penguin rookeries.

For more on glacier recession and around the world, please see Ice Under Fire, the Mountain Glacier section.

Pushing the Boundaries of Life: Antarctica

A colony of Adelies on Humble Island, one of eight islets off Anvers Island where thousands of Adelies have nested for some 600 years. Over the last 25 years these Adelie colonies have declined sharply. Chinstrap penguins are moving rapidly into Adelie territory. Archaeological digs in penguin colonies indicate there probably were no chinstraps in this area until about 50 years ago, when average temperatures began to rise.

Ornithologist Bill Fraser stands on the smooth pebbly surface of a former large colony of Adelie penguins on Torgersen Island. Unlike the colony in the photo above, this nesting site has been used by fewer and fewer penguins over recent years. Analyzing climate data, island topography, and breeding statistics, Fraser believes climate change caused the loss of half of its 16,000 nesting Adelies. Warming temperatures and more open water make for greater snowfall and more difficult hunting for krill, affecting nesting success. These changes are seen in other Adelie colonies on the Antarctic peninsula, but elsewhere in Antarctica, climate change either is favorable to the birds or is not affecting them.

A male Adelie penguin, back from a long feeding trip, disgorges krill for its chick. Krill develop best under seasonal ice, so thinner, less extensive winter ice can reduce the size of the shrimp-like Antarctic staple. The tiny radio transmitter on this bird's back allows Dr. Fraser to monitor how far and for how long penguins hunt for food. For some colonies, hunting times are becoming longer and longer as diminished seasonal sea ice extends the distance from rookery to feeding ground.

Although the Adelie penguin is not threatened as a species by global warming or man-caused problem so far, many species of this bird are. In a landmark decision that nevertheless fell short of conservationists' proposals, the US Fish and Wildlife Service proposed seven penguin species as candidates for 'threatened" status under the Endangered Species Act.

Included in the December 2008 document are the African penguin, yellow-eyed penguin, white-flippered penguin, Fiordland crested penguin, Humboldt penguin, and erect-crested penguin and a portion of the range of the southern rockhopper penguin. However, the ruling denied listing for the majority of the range of the southern rockhopper penguin, as well as for the northern rockhopper penguin, macaroni penguin, and emperor penguin.

The emperors, the ones in the film "March of the Penguin" are among species which are losing numbers apparently due to warming seas, reduced summer sea ice, and lack of their prime food, krill. If the candidate species are found by additional study and public comment to be worthy of being listed, they will receive protection under the Endangered Species Act sometime in 2009.
http://www.worldviewofglobalwarming.org/pages/antarctica2.html

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Global Warming

Global Warming

Upsetting a delicate balance In the past the Earth's climate has changed as a result of natural causes in our atmosphere.

The changes we are witnessing and those that are predicted are largely due to human behaviour: we are burning fossil fuels, and heating up the planet at the same time. We blow exponential amounts of carbon dioxide (CO₂) into the atmosphere every year – 29 billion tonnes of it (2004) and rising – and this warms the globe.

Since the Industrial Revolution, humans have been burning fossil fuels on a massive scale. We use this energy, almost without care for the consequences, to run vehicles, heat homes, conduct business, and power factories.

Burning fossil fuels releases carbon dioxide stored millions of years ago as oil, coal or natural gas. In the last 200 years we have burned a large part of these stores, resulting in an increase in CO₂ in our atmosphere. Deforestation also releases CO₂ stored in trees and in the soil.

The increase of CO₂ in the atmosphere thickens the 'greenhouse blanket', with the result that too much heat is trapped into the Earth's atmosphere. This causes global warming: global temperatures rise and cause climate change.

Note: CO₂ is the most important gas causing global warming. Others include methane (CH₄), nitrous dioxide (NO₂), and several artificial gases (Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs); and Sulphur hexafluoride (SF₆). These 6 groups are accounted for under the Kyoto Protocol.

Sea Ice Extent Comparison at the North Pole - mimumum ice reach comparison between 1979 and 2005. © NASA

Current statistics

Data from the World Resources Institute show that humans have added 2.3 trillion tonnes of CO₂ to the atmosphere in the last 200 years. Half of this amount was added in the last 30 years. The largest absolute increase in CO₂ emissions occurred in 2004, when burning fossil fuels alone added more than 28 billion tonnes to the atmosphere.
Source: WRI, Navigating the numbers, based on data from IEA, EIA, Marland et al, and BP.

Overall, the concentration of CO₂ in the atmosphere has increased by 31% since 1750, i.e. since the Industrial Revolution. CO₂ emissions are now around 12 times higher than in 1900 as the world burns more and more coal, oil and gas for energy. A 1999 study by Mann et al. shows the dramatic increase in temperature in the Northern Hemisphere in the last 50 years. This well-known hockey stick curve has been validated by numerous other scientists.

The (not too distant) future

We simply cannot continue pumping CO₂ into the atmosphere without curbs and controls. Even with the best case scenario for the increase in CO₂ emissions it is predicted that the concentration of CO₂ in the atmosphere will reach double the level of before the Industrial Revolution by 2100. The worst case scenario brings this doubling forward to 2045 – less than 40 years from now! The Third Assessment Report of the UN's Intergovernmental Panel on Climate Change (IPCC) predicts global temperature rises by the end of the century of between 1.4°C and 5.8°C.

The Earth’s climate is driven by a continuous flow of energy from the sun. Heat energy from the sun passes through the Earth’s atmosphere and warms the Earth’s surface.

The fragile atmosphere protects us from the universe.

As the temperature increases, the Earth sends heat energy (infrared radiation) back into the atmosphere. Some of this heat is absorbed by gases in the atmosphere, such as carbon dioxide (CO₂) , water vapour, methane, nitrous oxide, ozone and helacarbons.

The greenhouse effect

These gases, which are all naturally occurring, act as a blanket, trapping in the heat and preventing it from being reflected too far from the Earth. They keep the Earth's average temperature at about 15°C: warm enough to sustain life for humans, plants and animals. Without these gases, the average temperature would be about minus 18°C - too cold for higher life. This natural warming effect is also sometimes called the greenhouse effect.

Carbon dioxide (CO₂)

CO₂ is the most significant of the gases in our atmosphere which keep the Earth warm. Four billion years ago its concentration in the atmosphere was much higher than today (80% compared to today's 0.03%), but most of it was removed through photosynthesis over time. All this carbon dioxide became locked in organisms and then minerals such as oil, coal and petroleum inside the Earth's crust.

The natural carbon dioxide cycle

A natural carbon dioxide cycle keeps the amount of CO₂ in our atmosphere in balance. Decaying plants, volcanic eruptions and the respiration of animals release natural CO₂ into the atmosphere, where it stays for about 100 years. It is removed again from the atmosphere by photosynthesis in plants and by dissolution in water (for instance in the oceans).

The amount of naturally produced CO₂ is almost perfectly balanced by the amount naturally removed. Even small changes caused by human activities can upset this equilibrium.

The world is warming faster than at any time in the last 12,000 years. The 1990s was the hottest decade in the past millennium.

As global warming tightens its grip, the effects are being felt from the highest mountain peaks to the depths of the oceans. In just the last few years there are numerous examples of how this is affecting people and nature all over the world.

• Global warming is melting glaciers in every region of the world, putting millions of people at risk from floods, droughts and lack of drinking water.
  
  
• March 2006 showed the smallest Arctic sea ice cover ever measured. In the space of one year an area about the size of Italy was lost. The National Snow and Ice Data Center in the United States found that sea ice extent had reduced by 300,000 square km in comparison to March 2005, itself already a record low year.
  
  
• 2003, Scotland's hottest year on record, saw hundreds of adult salmon die in Scotland’s famous fisheries, as rivers became too warm for salmon to be able to extract enough oxygen from the water.
  
  
• Coral reefs around the world have been severely damaged by unusually warm ocean temperatures. The Caribbean saw its warmest ever ocean temperatures in 2005, combined with the worst coral bleaching ever. At the current rate of degradation, the entire Great Barrier Reef could be dead within a human lifetime.
  
  
• Cities like Athens, Chicago, Milan, New Delhi and Paris have sweltered under heatwaves. The 2003 summer heatwave in Europe killed 14,800 people in France alone, according to official figures released in September 2003. The French National Institute for Health and Medical Research said that the death rate was on average 60% higher than usual.
  
  
• Summer temperatures in European capitals have increased by up to 2°C over the last 30 years, a WWF report showed.
  
  
• Rising sea levels threaten entire nations on low-lying islands in the Pacific and Indian Oceans. Read how WWF South Pacific tries to help concerned villagers.
  
  
• A report released by WWF and leading meteorologists shows that human-induced global warming was a key factor in the severity of the 2002 drought in Australia, generally regarded as the worst ever.

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What is Climate Change ?

Earth’s climate is changing. Greenhouse gases are accumulating. Human activities are the cause.

Further Resources

» The Intergovernmental Panel on Climate Change (IPCC) » Summary for Policymakers of the Synthesis Report of the IPCC Fourth Assessment Report

The build-up of greenhouse gases (GHGs) threatens to set the Earth inexorably on the path to a unpredictably different climate. The Intergovernmental Panel on Climate Change (IPCC) says many parts of the planet will be warmer. Droughts, floods and other forms of extreme weather will become more frequent, threatening food supplies. Plants and animals which cannot adjust will die out. Sea levels are rising and will continue to do so, forcing hundreds of thousands of people in coastal zones to migrate.

One of the main GHGs which humans are adding to the atmosphere, carbon dioxide (CO2), is increasing rapidly. Around 1750, about the start of the Industrial Revolution in Europe, there were 280 parts per million (ppm) of CO2 in the atmosphere. Today the overall amount of GHGs has topped 390 ppm CO2e (parts per million of carbon dioxide equivalent – all GHGs expressed as a common metric in relation to their warming potential) and the figure is rising by 1.5–2 ppm annually. Reputable scientists believe the Earth’s average temperature should not rise by more than 2°C over pre-industrial levels. Among others, the European Union indicated that this is essential to minimize the risk of what the UN Framework Convention on Climate Change (UNFCCC) calls dangerous climate change and keep the costs of adapting to a warmer world bearable. Scientists say there is a 50 per cent chance of keeping to 2°C if the total GHG concentration remains below 450 ppm.

WHAT CAN YOU DO?

Climate change is here to stay. But it is still in our power – as individuals, businesses, cities and governments – to influence just how serious the problem will become.

Further Resources

» Climate Neutral Network Website » Kick the Habit: A UN Guide to Climate Neutrality » Twelve Steps to Help You Kick the CO2 Habit » Climate Change Adaptation and Mitigation in the Tourism Sector

Whether you are an individual, an organization, a business or a government, there are a number of steps you can take to reduce your carbon emissions, the total of which is described as your carbon footprint. You may think you don’t know where to begin, but by reading this, you have already begun.

Indeed, some quite simple ‘no regrets’ measures can more than halve the daily emissions of an individual, with even bigger cuts possible if sectors like power suppliers and automobile makers as well as aviation and appliance manufacturers contributed more to the greening of global lifestyles.

Individuals who reduce their energy consumption and thus their climate impact also save money. On a more macro-economic level, economic opportunities arise from measures taken to reduce GHGs: insulating buildings for example will not only save energy costs, but also give the building sector an enormous boost and create employment. While some sectors might suffer increased costs, many will seize the opportunity to innovate and get a step ahead of their competitors in adapting to changed market conditions.

Many companies, cities, organizations and indeed whole countries are embarking on strategies to achieve even zero emission businesses, communities and economies. A great deal of this transition to a green economy is being federated and empowered under the banner of UNEP's Climate Neutral Network (CN Net) which was launched in February 2008.

Some low-carbon lifestyle choices at home, in the office and when traveling include:

• Waking up with a traditional wind-up alarm clock rather than the beep of an electronic one - this can save someone almost 48 grams (g) of CO2 each day;
• Choosing to dry clothes on a washing line versus a tumble dryer - a daily carbon diet of 2.3 Kg of CO2;
• Replacing a 45-minute workout on a treadmill with a jog in a nearby park. This saves nearly 1 Kg of the main greenhouse gas;
• Opting for non-electric toothbrush will avoid nearly 48g of CO2 emissions;
• Heating bread rolls in a toaster versus an oven for 15 minutes saves nearly 170g of CO2;
• Switching from regular 60-Watt light bulbs to energy-saving ones will produce four times less greenhouse gas emissions;
• Taking the train rather than the car for a daily office commute of as little as 8 km will save a big 1.7 Kg of CO2;
• Shutting down your computer and flat screen both during lunch break and after working hours will cut CO2 emissions generated by these appliances by one-third;
• Investing in a water-saving shower head will not only save 10 liters of water per minute, but will also slash CO2 emissions resulting from a three-minute hot shower by half;
• Reducing the weight of goods and items carried onboard by airline passengers to below 20Kg could cut global GHG emissions by two million tonnes of CO2 a year.

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