CLIMATE CHANGE AND YOU

ARE WE CONVERSANT WITH CLIMATE CHANGE?
DREAM BASIC –UNFOLD MAGIC-SAVE EARTH.
Climate change is a problem related to changes in the concentration of the
greenhouse gases (watervapour, co2,ch4,n2o,cfcs)which trap infrared
radiation from the earth’s surface and thus cause the greenhouse effect.
This effect is a natural phenomenon, which helps maintain a stable
temperature and climate on earth. Changes in solar cycle of 11 years,
changes in earths orbit and its variations, aerosols and human factors,
abrupt change in land use, atmospheric aerosols lead to climate change.
The IPCC was established to provide the decision-makers and others
interested in climate change with an objective source of information about
climate change. The IPCC does not conduct any research nor does it monitor
climate related data or parameters. Its role is to assess on a
comprehensive, objective, open and transparent basis the latest
scientific, technical and socio-economic literature produced worldwide
relevant to the understanding of the risk of human-induced climate change,
its observed and projected impacts and options for adaptation and
mitigation.
Climate change is a very complex issue: policymakers need an objective
source of information about the causes of climate change, its potential
environmental and socio-economic consequences and the adaptation and
mitigation options to respond to it. This is why WMO and UNEP established
the Intergovernmental Panel on Climate Change (IPCC) in 1988.
According to the “Principles Governing IPCC Work”, published at the 25th
Session in Mauritius in April 2006, the IPCC's role is:
1)To assess on a comprehensive, objective, open and transparent basis the
scientific, technical and socio-economic information relevant to
understanding the scientific basis of risk of human-induced climate
change.
2)To monitor the potential impacts of such human induced climate change.
3)To highlight the options available to adapt to such climate change and
the means to mitigate against such changes.
4)The issuing of major reports, including Assessment Reports, Special
Reports and Methodology Reports.
Despite the global community having agreed to combating
anthropogenic climate change through universal acceptance of the UN
Framework Convention on Climate Change (UNFCCC) as far back as in 1992,
global GHG emissions continue to increase, with a substantial jump of 70%
between 1970 and 2004. Within a long-term perspective the atmospheric
concentrations of CO2 and CH4 in 2005 exceeded by far the natural range over
the last 650,000 years. The last time the polar regions were significantly
warmer
than present for an extended period (about 125,000 years ago), reductions in
polar ice volume led to 4 to 6 metres of sea level rise.
Transport is important as well, with the following currently available
options listed:
More fuel efficient vehicles; hybrid vehicles; cleaner diesel vehicles;
biofuels; modal shifts from road
transport to rail and public transport systems; non-motorised transport
(cycling, walking); land-use and
transport planning. The effect of mitigation options may be counteracted
by growth in the sector.
Market forces alone, including rising fuel costs, are therefore not
expected to lead to significant
emission reductions.
The waste sector can also positively contribute to GHG mitigation at low
cost and promote sustainable
development.
In order to stabilize the concentration of GHGs in the atmosphere,
emissions would need to peak.
This assessment, of the likely changes to the hydrological cycle from
global warming, is largely derived from published studies
of the use of General Circulation Models (GCMs) coupled with smaller,
catchment scale, hydrologic models.
GCMs are based on physical laws represented by mathematical equations that
are solved on a three-dimensional grid over the
globe. The solutions are obtained using high-powered supercomputers.
Generally speaking, the greater the power of the
supercomputer the finer the grid and/or the more complex the model that
can be integrated forward in time to provide an
estimate of the climate when greenhouse gas concentrations (for example)
are increased according to some pre-specified
scenario.
There are a number of major drawbacks in using these models.
The first relates to scenarios.
Any projection of future climate change is based on scenarios. These
scenarios are idealisations of the rates at which
greenhouse gases will be emitted in the future and there are, of course,
widely varying estimates of just what these emission
rates will be.
Secondly, when studying the impacts of changes in the hydrological cycle
there is a scale mismatch between the GCMs, that
might only have a grid point every 200 km or so, and the catchment scale
hydrologic models, where the entire catchment might
fit within three, or less, grid points of the GCM.
Thirdly, there is a temporal scale issue. Generally, GCMs provide monthly
mean data, whereas catchment scale models
require hydrologic data (rainfall or streamflow) on daily or hourly time
scales.
Nevertheless, the TAR WGII report summarises the trends in precipitation
due to global warming, as assessed from published
reports of combined GCM/hydrologic model studies. According to these,
there is likely to be:
(1) an increase in annual precipitation in high- and mid-latitudes and
most equatorial regions; a general decrease of annual precipitation in the
sub-tropics;
(2) small changes in annual precipitation, even by 2080, when compared
with natural multi-decadal variability;
(3) increased frequency of heavy rainfall events as the world warms;
(4) a smaller proportion of precipitation may fall as snow (decreasing
snow pack), thereby increasing winter runoff,
but diminishing spring (snow-pack melt) run-off commensurately.
�� Aviation Traffic: Passenger traffic has grown since 1960
at nearly 9% per year, 2.4 times the average Gross
Domestic Product over the same time period. Global passenger air travel is
projected to grow by about 5% per
year between 1990 and 2015, where-as total aviation fuel use (passenger,
freight and military) is projected to
increase by about 3% per year, the difference being due largely to
improved aircraft efficiency. The
assessment developed a number of long-term (1990 – 2050) emissions
scenarios for both subsonic and
supersonic aircraft, including a reference scenario which used mid-range
assumptions for each of the key
determinants, using a range of assumptions for economic and traffic growth
and fuel burn, which is dependent
upon rates of change in technology and air traffic management.
AVIATION CREATING HAVOC IN CLIMATE CHANGE:
1) Aircraft Emissions: Aircraft emit gases and particles directly into the
upper troposphere and lower
stratosphere where they have an impact on atmospheric composition. These
gases and particles alter the
concentration of greenhouse gases, including carbon dioxide, ozone, water
vapor and methane, trigger the
formation of condensation trails (otherwise known as contrails), and may
increase cirrus cloudiness – all of
which contribute to climate change.
2) Radiative Forcing: The major contributors from aircraft emissions to
the radiative forcing, which is a measure
of a change in climate, are carbon dioxide, ozone, methane (negative
effect) and contrails, with minor
contributions from water vapor, sulfate aerosols (negative effect) and
soot. The contribution from cirrus
clouds is projected to be positive and could be quite significant, but our
current lack of scientific
understanding precludes a quantitative assessment of its contribution.
While the contributions from carbon
dioxide, ozone, methane (opposite sign) and contrails are comparable in
magnitude, the uncertainties
associated with ozone, methane and contrails are much larger than those
associated with carbon dioxide.
Current Impact of Aviation Emissions on Climate: The best estimate of the
radiative forcing in 1992 by
aircraft is 0.05 Wm-2 (0.01 to 0.1 Wm-2) or about 3.5% of the total
radiative forcing by all human activities.
These estimates of forcing combine the effects of changes in all
greenhouse gas concentrations, aerosols and
line-shaped contrails, but do not include possible changes in cirrus.
From the above discussions it is quite clear that apart from natural
inflictions of elements inducing climate change human induced factors
primarily globalization, cross binding parameters of technological shifts
have facilitated the rapid change in the climate where global warming is a
serious concern. Its not only the duty henceforth of any international
institution to monitor the progress but its human element which is basic
and should be proactive in stopping the menace of climate rollover. Proper
awareness programmes, good governance, civic senses, and a responsibility
for a good earth is all we require to fight the terror of environmental
disaster. It can be well said that research alone is insufficient, so is
monetory funding and latest technologies; the real magic is in our
hands……..lets unfold the magic and breathe and dream a healthier EARTH.