Global warming is caused by human-induced greenhouse gas emissions and is causing average global temperatures to rise. If emissions continue at their current rate, global temperatures could increase by 1.4-5.8ยฐC by 2100, with devastating consequences such as more extreme weather, rising sea levels, species extinction, and major impacts on human societies. However, immediate action to reduce emissions through sustainable practices like renewable energy and energy efficiency could help limit global warming to less severe levels.
2. ๏ Measurements of temperature taken by instruments all over the
world, on land and at sea have revealed that during
the 20th centurythe Earthโs surface and lowest part of the
atmosphere warmed up on average by about 0.6ยฐC. During this
period, man-made emissionsof greenhouse gases, including carbon
dioxide,methane and nitrous oxide have increased, largely as a
result of the burning of fossil fuelsfor energy and transportation, and
land use changes including deforestation for agriculture. In the last
20 years, concern has grown that these two phenomena are, at least
in part, associated with each other. That is to say, global warming is
now considered most probably to be due to the increases in
greenhouse gas emissions and concurrent increases in atmospheric
greenhouse gasconcentrations, which have enhanced the
Earth's natural greenhouse effect. Whilst other natural causes
of climate change can cause global climate to change over similar
periods of time, computer models demonstrate that in all probability
there is a real discernible human influence on the global climate.
3. ๏ If the climate changes as current computer models have projected,
global average surface temperature could be anywhere from 1.4 to
5.8ยฐC higher by the end of the 21st century than in 1990. To put this
temperature change into context, the increase in global average
surface temperature which brought the Earth out of the last major ice
age 14,000 years ago was of the order of 4 to 5ยฐC. Such a rapid
change in climate will probably be too great to allow
manyecosystems to suitably adapt, and the rate of species extinction
will most likely increase. In addition to impacts on wildlife and
species biodiversity, humanagriculture, forestry, water
resources and health will all be affected. Such impactswill be related
to changes in precipitation (rainfall and snowfall), sea level, and the
frequency and intensity of extreme weather events, resulting from
global warming. It is expected that the societies currently
experiencing existing social, economic and climatic stresses will be
both worst affected and least able to adapt. These will include many
in the developing world, low-lying islands and coastal regions, and
the urban poor.
4. ๏ The Framework Convention on Climate Change (1992) and the Kyoto
Protocol(1997) represent the first steps taken by the international community
to protect the Earth's climate from dangerous man-made interference.
Currently, nations have agreed to reduce greenhouse gas emissions by an
average of about 5% from 1990 levels by the period 2008 to 2012. The UK,
through its Climate Change Programme, has committed itself to a 12.5% cut
in greenhouse gas emissions. Additional commitments for further
greenhouse gas emission reduction will need to be negotiated during the
early part of the 21st century, if levels of greenhouse gas concentrations in
the atmosphere are to be stabilised at reasonable levels. Existing and future
targets can be achieved by embracing the concept ofsustainable
development - development today that does not compromise the
development needs of future generations. In practical terms, this means
using resources, particularly fossil-fuel-derived energy, more efficiently, re-using
and recycling products where possible, and developing renewable
forms of energy which are inexhaustible and do not pollute the atmosphere.
๏ http://www.enviropedia.org.uk/Global_Warming/Global_Warming_Introductio
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5. ๏ Global warming is expected to have far-reaching, long-lasting
and, in many cases, devastating consequences for planet
Earth.
๏ For some years, global warming โ the gradual heating of
Earth's surface, oceans and atmosphere โ was a topic of
heated debate in the scientific community.
๏ But the overwhelming consensus of researchers today is that
global warming is real and is caused by human activity,
primarily the burning of fossil fuels that pump carbon dioxide
(CO2), methane and other greenhouse gases into the
atmosphere. In fact, a major report released Sept. 27, 2013,
by the Intergovernmental Panel on Climate Change (IPCC)
stated that scientists are more certain than ever of the link
between human activities and global warming.
๏ Additionally, global warming is having a measurable effect on
the planet right now.
6. ๏ One of the most immediate and obvious impacts of
global warming is the increase in temperatures
around the world. The average global temperature
has increased by about 1.4 degrees Fahrenheit
(0.8 degrees Celsius) over the past 100 years,
according to the National Oceanic and
Atmospheric Administration (NOAA).
๏ Since recordkeeping began in 1895, the hottest
year on record for the 48 contiguous U.S. states
was 2012. Worldwide, 2012 was also the 10th-warmest
year on record, according to NOAA. And
nine of the warmest years on record have occurred
since 2000.
7. ๏ Scientists have found that the number and severity of extreme
weather events โ record-breaking high or low temperatures,
high rainfall events or intense storms โ are an effective
measure of climate change and global warming.
๏ The U.S. Climate Extremes Index (CEI) was established in
1996 to track these events. The number of extreme weather
events that are among the most unusual in the historical
record, according to the CEI, has been rising over the last four
decades, according to NOAA.
๏ Scientists project that extreme weather events, such as heat
waves, droughts, blizzards and rainstorms will continue to
occur more often and with greater intensity due to global
warming, according to Climate Central.
8. ๏ Climate models forecast that global warming will cause
climate patterns worldwide to experience significant
changes. These changes will likely include major shifts
in wind patterns, annual precipitation and seasonal
temperatures variations.
๏ And because high levels of greenhouse gases in the
atmosphere are likely to remain high for many years,
these changes are expected to last for several
decades or longer, according to the Environmental
Protection Agency (EPA).
๏ In the northeastern United States, for example, climate
change is likely to bring increased annual rainfall, while
in the Pacific Northwest, summer rainfall is expected to
decrease.
9. ๏ Since 1970, the area of snow cover in the United States has
steadily decreased, according to the EPA, and the average
temperature of permafrost (soil that's at or below freezing
temperature) has grown warmer.
๏
๏ One of the most dramatic effects of global warming is the
reduction in Arctic sea ice: In 2012, scientists saw the smallest
amount of Arctic ice cover ever recorded. Most analyses
project that, within a matter of years, the Arctic Sea will be
completely ice-free during the summer months.
๏ Glacial retreat, too, is an obvious effect of global warming.
Only 25 glaciers bigger than 25 acres are now found in
Montana's Glacier National Park, where about 150 glaciers
were once found, according to the U.S. Geological Survey. A
similar trend is seen in glacial areas worldwide.
10. ๏ Melting polar ice in the Arctic and Antarctic
region, coupled with melting ice sheets and
glaciers across Greenland, North America,
South America, Europe and Asia, are
expected to raise sea levels significantly. And
humans are mostly to blame: In the IPCC
report released on Sept. 27, 2013, cimate
scientists said they are at least 95 percent
certain that humans are to blame for warming
oceans, rapidly melting ice and rising sea
levels, changes that have been observed
since the 1950s.
11. ๏ Global sea levels have risen about 8 inches since 1870,
according to the EPA, and the rate of increase is expected to
accelerate in the coming years. If current trends continue,
many coastal areas โ where roughly half of the Earth's
human population lives โ will be inundated.
๏ Researchers project that by 2100, average sea levels will be
2.3 feet higher in New York City, 2.9 feet higher at Hampton
Roads, Va., and 3.5 feet higher at Galveston, Texas, the EPA
reports. According to the Sept. 27 IPCC report, if greenhouse
gas emissions remain unchecked, sea levels could rise by as
much as 3 feet (0.9 meters) by 2100. That estimate is an
increase from the estimated 0.9 to 2.7 feet (0.3 to 0.8 meters)
that was predicted in the 2007 IPCC report for future sea level
rise.
12. ๏ As levels of atmospheric carbon dioxide (CO2)
increase, the oceans absorb some of that CO2, which
increases the acidity of seawater. Since the Industrial
Revolution began in the early 1700s, the acidity of the
oceans has increased about 25 percent, according to
the EPA.
๏ Because acids dissolve calcium carbonate, seawater
that's more acidic has a deleterious effect on
organisms with shells made of calcium carbonate,
such as corals, mollusks, shellfish and plankton.
๏ If current ocean acidification trends continue, coral
reefs are expected to become increasingly rare in
areas where they are now common, including most
U.S. waters, the EPA reports.
13. ๏ The effects of global warming on the Earth's
ecosystems are expected to be profound and
widespread. Many species of plants and
animals are already moving their range
northward or to higher altitudes as a result of
warming temperatures, according to a report
from the National Academy of Sciences.
๏ Additionally, migratory birds and insects are
now arriving in their summer feeding and
nesting grounds several days or weeks earlier
than they did in the 20th century, according to
the EPA.
14. ๏Warmer temperatures will also expand the
range of many disease-causing pathogens
that were once confined to tropical and
subtropical areas, killing off plant and animal
species that formerly were protected from
disease.
๏ These and other impacts of global warming, if
left unchecked, will likely contribute to the
disappearance of up to one-half of the Earth's
plants and one-third of animals from their
current range by 2080, according to a 2013
report in the journal Nature Climate Change.
15. ๏ As dramatic as the effects of climate change are expected to be on the natural world, the
projected changes to human society may be even more devastating.
๏ Agricultural systems will likely be dealt a crippling blow: Though growing seasons in some
areas will expand, the combined impacts of drought, severe weather, lack of snowmelt,
greater number and diversity of pests, lower groundwater tables and a loss of arable land
could cause severe crop failures and livestock shortages worldwide.
๏ This loss of food security might, in turn, create havoc in international food markets and
could spark famines, food riots, political instability and civil unrest worldwide, according to a
number of analyses from sources as diverse as the U.S Department of Defense, the Center
for American Progress and the Woodrow Wilson International Center for Scholars.
๏ The effect of global warming on human health is also expected to be serious: The American
Medical Association has reported an increase in mosquito-borne diseases like malaria and
dengue fever, as well as a rise in cases of chronic conditions like asthma, are already
occurring, most likely as a direct result of global warming.
๏ Many of these expected impacts are the result of exhaustive scientific research and climate
models, and the fact that most of them are already being observed gives additional
credibility to the projected effects of global warming and climate change.
๏ http://www.livescience.com/37057-global-warming-effects.html
16. ๏ 1. CONCLUSION In conclusion, Global Warming is a serious
problem that it would reduce if people started from now being
conscious about what is happening in the world and the
consequences of our actions.
๏ 2. HOW TO STOP GLOBAL WARMING ๏ถ We cannot wait for
governments to find a solution for this problem, each person can
bring important help by adopting a responsible lifestyle, starting from
little daily things.
๏ 3. TAKE TO HELP REDUCE GLOBAL WARMING.1.-Reduce,
Reuse, Recycle 2.-Use Less Heat and Air ConditioningRecycle
๏ 4. STOP GLOBAL WARMING3. Change a Light Bulb 4.-Drive less
๏ 5. STOP GLOBAL WARMING 6. Use Less Hot Water5.-Buy energy-efficient
products
๏ 6. STOP GLOBAL WARMING7.-Use the "Off" Switch 8.- Plant a tree
๏ 7. STOP GLOBAL WARMING9.- Avoid pollution 10. Encourage
Others to Conserve
๏ http://www.slideshare.net/GuadyssG/conclusion-10975821
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17. ๏ 1 2009 Ends Warmest Decade on Record. NASA Earth Observatory Image of the Day, 22 January 2010.
๏ Jump up^ "Warming of the climate system is unequivocal" p.2, IPCC, Climate Change 2013: The
Physical Science Basis - Summary for Policymakers, Observed Changes in the Climate System, p. 2,
in IPCC AR5 WG1 2013.
๏ Jump up^ "Ocean warming dominates the increase in energy stored in the climate system, accounting
for more than 90% of the energy accumulated between 1971 and 2010." p.6,IPCC, Climate Change 2013:
The Physical Science Basis - Summary for Policymakers, Observed Changes in the Climate System, p. 6,
in IPCC AR5 WG1 2013.
๏ Jump up^ Riebeek, H. (June 3, 2010). "Global Warming: Feature Articles". Earth Observatory, part of the
EOS Project Science Office located at NASA Goddard Space Flight Center."Global warming is the
unusually rapid increase in Earth's average surface temperature over the past century primarily due to the
greenhouse gases released as people burn fossil fuels."
๏ ^ Jump up to:a b America's Climate Choices. Washington, D.C.: The National Academies Press. 2011.
p. 15. ISBN 978-0-309-14585-5. "The average temperature of the Earth's surface increased by
about 1.4 ยฐF (0.8 ยฐC) over the past 100 years, with about 1.0 ยฐF (0.6 ยฐC) of this warming occurring over
just the past three decades."
๏ Jump up^ "Each of the last three decades has been successively warmer at the Earth's surface than any
preceding decade since 1850." p.3, IPCC, Climate Change 2013: The Physical Science Basis - Summary
for Policymakers, Observed Changes in the Climate System, p. 3, in IPCC AR5 WG1 2013.
๏ ^ Jump up to:a b "Three different approaches are used to describe uncertainties each with a distinct form
of language. * * * Where uncertainty in specific outcomes is assessed using expert judgment and
statistical analysis of a body of evidence (e.g. observations or model results), then the following likelihood
ranges are used to express the assessed probability of occurrence: virtually certain >99%; extremely
likely >95%; very likely >90%; likely >66%;......" IPCC, Synthesis Report, Treatment of Uncertainty,
in IPCC AR4 SYR 2007.
๏ http://en.wikipedia.org/wiki/Global_warming#Citations