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Three to four billion years ago
Solar Energy effects on earth:
Present Environment Issues:
Three to four billion years ago the sun emitted only 70% as much power as it does today. If the atmospheric
composition had been the same as today, liquid water should not have
existed on Earth. However, there is evidence for the presence of water on
the early Earth, in the Hadean and Archeaneons, leading to what is known
as the faint young Sun paradox. Hypothesized solutions to this paradox
include a vastly different atmosphere, with much higher concentrations
of greenhouse gases than currently exist. Over the following
approximately 4 billion years, the energy output of the sun increased and
atmospheric composition changed. The Great Oxygenation Event -
oxygenation of the atmosphere- around 2.4 billion years ago was the
most notable alteration. Over the next five billion years the sun's ultimate
death as it becomes a red giant and then a white dwarfwill have large
effects on climate, with the red giant phase possibly ending any life onEarth that survives until that time.
Solar output also varies on shorter time scales, including the 11-year solar cycle and longer-term
modulations. Solar intensity variations are considered to have been influential in triggering the Little Ice Age, and
some of the warming observed from 1900 to 1950. The cyclical nature of the sun's energy output is not yet fully
understood; it differs from the very slow change that is happening within the sun as it ages and evolves. Research
indicates that solar variability has had effects including the Maunder Minimum from 1645 to 1715 A.D.., part of the
Little Ice Age from 1550 to 1850 A.D. which was marked by relative cooling and greater glacier extent than the
centuries before and afterward. Some studies point toward solar radiation increases from cyclical sunspot activity
affecting global warming, and climate may be influenced by the sum of all effects (solar variation, anthropogenic
radiative forgings, etc.).
Environmental issues are a global concern in the current scenario. This has
been prompted by the realization that human activities have already inflicted
much damage on the surrounding environment and it is high time that we
take stock of our activities to take care of the same. The sun is the
predominant source for energy input to the Earth. Both long- and short-
term variations in solar intensity are known to affect global climate.
There are too many environmental issues that require attention.These can be grouped under three broad categories. These global
warming, waste management and obviously the overuse of the natural
resources. Environmental pollution is not meant only air pollution but also
water, soil, noise and light pollution.
Scientists generally define the five components of earth's climate system
to include Atmosphere, hydrosphere, cry sphere, lithosphere (restricted to the
ENVIRONMENT PAST & PRESENTNVIRONMENT PAST & PRESENTNVIRONMENT PAST & PRESENTBhupinder SinghBhabour Sahib, Punjab
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surface soils, rocks, and sediments), and biosphere. Though the categories are different, the activities of one
category have consequently resulted in the impact mentioned in the other category. For example, the Earth once
had plentiful resources in the form of rich reserves of fossil fuels. But the overuse of these fossil fuels have not only
depleted their reserves but also led to excessive emission of greenhouse gases that have caused much harm to the
ozone layer. It is responsible for global warming that has resulted in climate changes all across the world that has had
an impact on life on Earth. We can discuss few issues as under:
This is one of the greatest problems that now
world is facing Air Pollution and causing grave
and irreparable damage to the ozone layer. Air
pollution is cause by the injurious smoke emitted
by cars, buses, trucks, trains, and factories,
namely sulpher dioxide, carbon monoxide and
nitrogen oxides. Evidence of increasing air
pollution is seen in lung cancer, asthma, allergies,
and various breathing problems along with
severe and irreparable damage to flora and
fauna. Chlorofluorocarbons (CFC), released fromrefrigerators, air-conditioners, deodorants and
insect repellents cause severe damage to the
Earth's environment. This gas has slowly
damaged the atmosphere and depleted the
ozone layer leading to global warming.
Water pollution caused industrial waste
products released into lakes, rivers, and
other water bodies. Humans pollute
water with large scale disposal of
garbage, flowers, ashes and other
household waste. Domestic sewage also
refers to waste water that is discarded
from households. Also referred to as
sanitary sewage, such water contains a
wide variety of dissolved and suspended
impurities. In many rural areas one can
still find people bathing and cooking in
the same water, making it incredibly
filthy. Acid rain further adds to water
pollution in the water. In addition tothese, thermal pollution and the
depletion of dissolved oxygen aggravate
the already worsened condition of the
water bodies. Water pollution can also indirectly occur as an offshoot of soil pollution through surface runoff and
leaching to groundwater. Burning of fossil fuels the emitted ash particles usually contain toxic metals (such as As or
Pb). Burning will also add a series of oxides including carbon dioxide to air and respectively water bodies.
Air Pollution:
Water pollution:
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Noise pollution
Soil pollution
Noise pollution, soil pollution and light pollution too are the damaging the environment at an alarming rate. Noise
pollution include aircraft noise, noise of cars, buses, and trucks, vehicle horns, loudspeakers, and industry noise, as
well as high-intensity sonar effects which are extremely harmful for the environment. Maximum noise pollution
occurs due to one of modern science's best discoveries the motor vehicle, which is responsible for about ninety
percent of all unwanted noise worldwide.
Soil pollution, which can also
be called soil contamination, is
a result of acid rain, polluted
water, fertilizers etc., which
leads to bad crops. Soil
contamination occurs when
chemicals are released by spill
or underground storage tank
leakage which releases heavy
contaminants into the soil.
T h e s e m a y i n c l u d e
hydrocarbons, heavy metals,
MTBE, herbicides, pesticides
and chlorinated hydrocarbons.
c a r r y i n g f e r t i l i z e r s ,
pesticides/insecticides/herbici
des and other pollutants into
water bodies such as lakes,
rivers, ponds). The usual effect
of this type of pollution consists in algae growing in affected water bodies. This is a sign of increased nitrates and
phosphates in water that could be harmful for human health. mining activities involve crushing the rock that usuallycontains many trace metals and sulfides. The left material may easily generate sulfuric acid in the presence of
precipitation water. Please, read more at Mining Sites.
Light Pollution includes light trespass, over-illumination and astronomical interference.
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods
ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of
events around that average (e.g., more or fewer extreme weather events). Climate change may be limited to a
specific region or may occur across the whole Earth.
The most general definition ofclimate change is a change in the statistical properties of the climate system when
considered over long periods of time, regardless of cause. Accordingly, fluctuations over periods shorter than a few
decades, such asEl Nio, do not represent climate change.
The term sometimes is used to refer specifically to climate change caused by human activity, as opposed to changes
in climate that may have resulted as part of Earth's natural processes. In this sense, especially in the context of
environmental policy, the term climate change has become synonymous with anthropogenic global warming.
Within scientific journals, global warming refers to surface temperature increases while climate change includes
global warming and everything else that increasing greenhouse gas levels will affect.