WRITING
Read the following text and, if necessary, take some notes so that you will be able to answer the questions in "Writing Activity - Climate Change (Part 2)"
Climate Change
Learn about
climate change. Prepare for the impacts, and reduce your carbon footprint.
The term 'climate change' usually
refers to recent changes in climate that have been observed since the early
1900s.
Climate is not the same as weather
Climate refers to the average
weather experienced in a region over a long period, typically 30 years. This
includes temperature, wind and rainfall patterns. The climate of the Earth is
not static, and has changed many times in the past - this is known as 'natural
variability'.
ü The
greenhouse effect
The earth is kept warm by the
greenhouse effect. Greenhouse gases such as carbon dioxide and methane are
naturally found in the atmosphere. They trap heat from the sun and keep our
planet warm enough to inhabit. Without greenhouse gases the Earth would be
about -18 degrees Celsius.
ü Human
impact on climate
There is a scientific consensus that
the recent observed rise in global temperature can only be explained by the
rise in greenhouse gas emissions caused by human activities.
Since the industrial revolution,
human activity, mostly the burning of fossil fuels, has resulted in the release
of large amounts of greenhouse gases into the atmosphere. This is enhancing the
greenhouse effect and pushing up global temperatures.
Average global temperatures have
already risen approximately one degree Celsius since pre-industrial levels, and
even if we could stop emitting all greenhouse gases tomorrow, they would
continue to rise by at least a further 0.6 degrees. Limiting temperature rise
to below two degrees is the internationally agreed target to avert dangerous
climate change.
There are clear signs that our world
is warming. We’ve had markedly higher global average temperatures over the last
decade, ice sheets and glaciers are melting and average river water
temperatures are increasing. Globally, the hottest ten years on record have all
been since 1990, and February 2010 was warmest on record for southern
hemisphere.
How will the climate change?
While a two degree rise in average
global temperatures doesn’t sound very dangerous, the effects will be unambiguous.
The present one degree rise has already shown severe impacts for our polar
regions and small island states. The Arctic is warming at about twice the global
average and sea ice in the region has declined dramatically over the past 30
years. Antarctica is now losing around 190 billion tonnes of ice a year. Small
island states, including 15 nations found in the Pacific, may face the most awful
and immediate consequences. Eighty percent of the Maldives lies three feet or
less above sea level and the predicted rise in sea level caused by global
warming could lead to their eventual disappearance.
Impacts of further warming of four
degrees or more are likely to include significant reductions in food production
in some regions, hundreds of millions of people without enough water, mass
species extinctions and sea levels rising by several metres.
In the planet, we will witness more
extreme events, such as flooding, storms, sea level rise and drought as well as
wetter warmer winters and hotter drier summers.
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