On Global Warming

1. Is the Arctic really melting?

2. Is global warming for real - how is the current climate change different from warm periods before?

3. In what ways do humans contribute to global warming?

4. How much do humans contribute to global warming?

5. Is the polar bear really going to become extinct?

6. Isn’t it too late to save the Arctic whatever we do?

7. What can people do?

8. Is it right that climate change in the Arctic could shut down the
Gulf Stream?

9. Doesn’t a shutdown of the Gulf Stream counteract the warming of
the Arctic?

10. Surely there are positive impacts of Arctic climate change?

11. Why does the Arctic warm faster than lower latitudes?


1. Is the Arctic really melting?
Yes, the Arctic is melting, ice-covered areas at sea, on rivers and lakes, and glaciers, have been shrinking for several decades. Permafrost is also melting in many areas. However, there are regional and seasonal variations:

Sea ice: The area covered with sea ice is twice as large in winter as in summer, but the relative reduction in sea ice extent is greatest in summer.

Observed changes: According to recent reports such as the Arctic Climate Impact Assessment (ACIA), the average sea ice extent in summer has declined by 15-20% over the past 30 years. This is the equivalent of more than 1.000.000 km2.
According to a study made for WWF by a NASA scientist, the current rate of melting is almost 10% per decade.

Future: Five climate models used by the Intergovernmental Panel on Climate Change (IPCC) show that on average summer sea ice extent will be reduced by more than 50% by 2100, with some models showing that the Arctic will be nearly ice-free in summer by that time.

In winter, the extent of sea ice will be closer to the current state; the greatest reduction predicted by any of the five models is 30%.

Glaciers: Glaciers throughout the Arctic - and in most of the world - are retreating. Alaskan glaciers are diminishing particularly fast, representing the greatest contribution by melting of glaciers to sea level rise yet measured.
At the Greenland Ice Sheet, the area that melted in summer was about 16% greater in 2002 than in 1979, breaking all previous records. A local warming over Greenland by 3°C, which we will see this century unless we cut CO2 emissions, will trigger a very rapid meltdown that over a few centuries could cause global the sea level to rise by seven meters.

Rivers and lakes: North-western Eurasian and North American lakes and rivers freeze later each year and thaw earlier than before.


2. Is global warming for real - how is the current climate change different from warm periods before?
It is right that the climate varies naturally. It is also right that the Arctic and the globe have seen warmer periods before. But there is a broad consensus among climate scientists that there has been an abnormally steep rise in global surface temperature since the industrial revolution (c. 1750), with a sharp rise at the end of the 20th century.

According to the Intergovernmental Panel on Climate Change (IPCC, a UN expert panel) the warmest century in the past thousand years was the 1900s, the warmest decade since weather monitoring started was the 1990s and there is 30% more carbon dioxide in the atmosphere now than before the industrial revolution, when people started burning fossil fuels
(coal, oil and gas).

As climate changes, the major way for plants and animal species to adapt is to migrate to new areas to find a suitable climate. Therefore, it is crucial that the rate of the climate change isn’t greater than the ability of the species to move and establish in a new place.


3. In what ways do humans contribute to global warming?
Humans contribute to climate change by adding greenhouse gases, primarily carbon dioxide (CO2), to the atmosphere. This happens first and foremost when we burn fossil fuels like coal, oil and gas, which have been stored underground or under the sea for millions of years and are not a part of the natural carbon cycle. Also, carbon is being added to the atmosphere when people change the use of lands, like when we log or burn forests.

4. How much do humans contribute to global warming?
The IPCC (see above) has estimated what the variations would have been like since the 1850s with and without man-made contributions, and the conclusion is clear: While we have seen a 0.7°C global average increase in temperature, the increase would have been close to zero without the human impact.


5. Is the polar bear really going to become extinct?
Last year more than 250 scientists produced the most comprehensive report on climate change in the Arctic (The Arctic Climate Impact Assessment). This report says that polar bears could become extinct by the end of this century unless actions to curb global warming are taken. They are very unlikely to survive as a species if there is an almost complete loss of summer sea ice cover, which is projected to occur before the end of this century by some climate models.


6. Isn’t it too late to save the Arctic whatever we do?
It’s not too late to save the Arctic - but we must act now. We have no time to lose.

The Arctic is the "barometer of global environmental health", as one Inuit leader put it. As the Arctic Climate Impact Assessment report explains, the Arctic warms faster than the rest of the world. If the globe warms on average by 2°C, the Arctic will carry the heaviest burden, with temperatures rising by 4°C or more. This will clearly mean that the region will see significant changes, such as an increased loss of sea ice habitat for polar bears and the invasion of new species in the southernmost parts of the Arctic.

Still, WWF thinks that it is possible to preserve the key biodiversity and cultural values of the Arctic. The dramatic impacts projected by ACIA are based on temperature rises from current levels (which as we know are already well above pre-industrial levels) and on the assumption that no action will be taken to reduce global warming, but if we take immediate action, most of the serious impacts can hopefully be avoided.

WWF thinks it is possible to reduce CO2 emissions to a level that ensures that global average temperatures stay below 2°C above pre-industrial levels and fall from there. This is at the heart of WWF’s climate change campaign - and the work of most other environmental NGOs, the European Union and the Alliance of Small Island States. To achieve this, global emissions will have to peak within the next decade or so and fall thereafter. Some temperature rise is already built into the climate system (because it takes time before the temperature responds to elevated CO2 concentrations), and therefore "staying below 2°C" requires deep cuts in CO2 emissions, and immediate action.


7. What can people do?
Industrialised countries must act. They should cut CO2 emissions and promote energy efficiency, renewable energy, fuel switching from coal to natural gas as a first step to renewable energy, and fuel-efficient vehicles.

In cooperation with arctic residents, we should develop solutions to adapt to the changes that occur as a result of climate change. These changes include the disappearance of habitats, the invasion of alien species, the occurrence of new diseases, and the destabilisation of everything from homes to oil pipelines. Governmental and private impact management in arctic regions should include social compensation for most vulnerable and affected communities.

Be cautious when considering new economic opportunities that result from climate change in the Arctic, like shipping and oil exploration (remember that burning hydrocarbons such as oil is the major cause of climate change), and work together to develop joint regulations to protect the interests of the environment, local residents and communities.


8. Is it right that climate change in the Arctic could shut down the
Gulf Stream?
Yes, this is possible. When warm water moves northwards from the tropics to the Atlantic Ocean in the Gulf Stream, it gets denser (and hence, heavier) and sinks. There are two reasons for this: it is cooled by the cold surface air, and gets saltier because the new sea ice is "fresher" than the ocean water. Water is denser the colder and saltier it is. The sinking water is replaced by more warm water from the tropics, and goes back to the tropics as a cold, deep ocean current. This phenomenon is the so-called thermo-haline circulation - also referred to as the "conveyor belt". The warm current (the Gulf Stream) is the reason why the western European coast enjoys a much warmer climate than expected when looking only at the latitude.

Climate change in the Arctic means that the water arriving to the Arctic Ocean is not cooled down as much. At the same time, more fresh water arrives into the ocean as the Greenland glaciers melt and runoff increases from the big Russian and Canadian rivers. This means that the surface water is warmer and fresher than it used to be, floating on top of the dense, salty water below. The driving force of the "conveyor belt" is then cut off, slowing down circulation, and thus reduces the rate of warming in north-western Europe for several decades, even as the rest of the planet warms more rapidly.

The chance for this happening is not great, but greater than previously thought, according to a recent high-level conference on climate change in England. The impacts would be enormous.


9. Doesn’t a shutdown of the Gulf Stream counteract the warming of
the Arctic?
Intuitively, we might think that a shutdown of the Gulf Stream would actually counteract the effect of a warming Arctic. However, it is important to remember that we are talking about a relative cooling in north-western Europe, which will take place in the context of an overall warming of the Arctic. If such an effect kicks in, it just goes to prove that the general warming of the Arctic is not uniform, and that it triggers complex cascade effects on regional climate


10. Surely there are positive impacts of Arctic climate change?
A number of the expected impacts of a warmer Arctic will allow for new economic activity, and will be seen as "good" by at least some interest groups. A key point, however, is that potential economic losses from climate change in the Arctic will be huge. A number of arctic coastal communities will have to relocate farther inland because of climate-related increases in storms, erosion and sea level; infrastructure such as buildings, roads and pipelines will become unstable as a result of melting permafrost; traditional food sources for indigenous communities will become less available; and fish species and populations in the Arctic will change dramatically.

Retreating sea ice, in combination with new technology, will open up previously inaccessible areas to oil and gas development and other extractive industries, for instance in the Barents Sea north of Norway and north-western Russia. A prolonged ice-free season along the Russian coast will make commercial shipping from Asia to Europe and North America possible through this route, the Northern Sea Route, for 90-100 days per year in 2080, instead of 20-30 days per year today. To shipping companies and manufacturers, this could mean increasing profits as this route is up to 40% shorter than current routes through the Suez and Panama Canals. To local people, it could mean more jobs.

However, these changes, although beneficial to some groups, create new challenges. Oil and gas extraction means prolonged dependency on fossil fuels, adding to emissions of greenhouse gases. This activity, as well as shipping, also creates a very high environmental risk in new and very vulnerable areas. Waters along the Northern Sea Route are hard to navigate, and oil spills that would result from grounded tankers in these areas would be catastrophic. Effects of such spills in cold seas generally last longer and are more severe than elsewhere, and there is no effective technology for cleaning up oil spills in partly ice-covered areas. Sovereignty over the ice-free areas and marine resources is likely to become a hot political issue if the Arctic Ocean is opened up. In addition, it will certainly be difficult in some instances for local communities to get their share in the
economic benefits.

WWF is therefore working to get arctic governments to develop an Arctic Treaty that covers environmental protection, shipping safety and rights to access, including traditional rights, and that establishes a precautionary approach when considering new economic activity.


11. Why does the Arctic warm faster than lower latitudes?
In short the reasons are:

As snow and ice melt, they reflect less sunlight, and the darker ocean surface absorbs more solar energy;

• As snow and ice melt, they reflect less sunlight, and the darker ocean surface absorbs more solar energy;
• More of the extra trapped energy goes directly into warming rather than into evaporation;
• The atmospheric layer that has to warm in order to warm the surface is shallower in the Arctic than on lower latitudes;
• As sea ice retreats, solar heat absorbed by the oceans is more easily transferred to the atmosphere;
• Alterations in atmospheric and oceanic circulation can
  increase warming.

"Thermo" refers to heat, "haline" refers to salinity


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