Climate change is simply define as change in global weather condition such as temperature, pressure etc. Climate change is a change in statistical distribution of weather pattern over time ranging from decades to millions of years. It may be change in weather conditions or distribution of weather around the average condition.
Climate change is caused by factors such as oceanic process (e.g. oceanic circulation) , biotic processes , variation in solar radiation , volcanic eruption , plate tectonic and human activities. Scientists actively work to understand past and future climate by using observation models and theoretical models. Floral and faunal record, glacial and periglacial process, stable isotope and other sediment analyses and sea level record serve to provide climate records that span the geologic award.
Causes On the broadest scale, the rate at which energy is received by the sun and energy release to space determines the equilibrium temperature and climate of the Earth. Factors that can change the climate are called climate forcing or forcing mechanism. These include the process such as variation solar radiation, variation in mountain building and continental drift & change in concentration of green house gases. Forcing mechanisms can be either internal or external. Internal forcing mechanisms are natural processes within the climate system itself.
External forcing mechanisms can be either natural (e.g. changes in solar output) or anthropogenic (e.g. increased emissions of greenhouse gases). Whether the initial forcing mechanism is internal or external, the response of the climate system might be fast, slow or a combination. Therefore, the climate system can respond abruptly, but the full response to forcing mechanisms might not be fully developed for centuries or even longer. Ocean variability:
Ocean is central part of climate system, some changes occurs on lager timescales than in atmosphere, massing hundreds of
times and having high thermal inertia. Short term fluctuation (from years to decades) represents climate variability instead of climate change such as Arctic oscillation and pacific oscillation. On large time period scales alternation to ocean processes such as thermohaline circulation play an important role in redistributing heat by carrying out extremely deep or slow movement of water. Life:
Life affects climate through its role in the water and carbon cycle and such mechanisms as cloud formation, weathering and evapotranspiration. Examples of how life may have affected past climate include: glaciations 2.3 billion years ago triggered by the evolution of oxygenic photosynthesis & global cooling over the past 40 million years cause by expansion of grass-grazer ecosystems. Solar output:
The sun is central source of energy to the life on earth. Long & short term variation in solar intensity affects the global climate. Three to four billion years ago the sun emitted only 70% power as it does today. If the composition of atmosphere had been the same as today, liquid water should not have existed on Earth at that time in past.
However, there is evidence for the presence of water on the early Earth, in the hadean & archean eons, leading to what is known as faint young Sun paradox. Hypothesized solutions to this paradox include a vastly different atmosphere, with much higher concentrations of greenhouse gases than currently exist at this time. Interestingly, a study in 2010 suggests, that the effects of solar variability on temperature throughout the atmosphere may be adverse to current expectations. Human activities:
The scientific opinion on climate change is that climate is changing and that these changes are in large part caused by human activities and it is largely irreversible. The most important in these factors is the increase in CO2 levels due to emissions from burning of fossil fuel followed by aerosols (particulate matter in the atmosphere) and cement manufacture.
Other factors, including land use, ozone depletion, animal agriculture and deforestation are also of concern in the roles they play – both separately and in conjunction with other factors – in affecting climate and measures of climate variables. Consequences of climate change:
There are number of consequences of climate change for example arctic sea ice loss, more heat related illness & disease, high temperature, wild life at risk etc.
Arctic sea ice loss:
The fall in arctic sea ice both in extent & thickness, over last few decades results in rapid climate change. Sea water freeze and that sea ice floats on sea surface. It covers large area in square miles in polar region, varying with sea season. It mainly affect sea life like polar bears. Economics loss:
Climate change greatly affects economic activities. Climate change would take 1 percent of GDP to lessen the most damaging effects of climate change, the report says. Globally more intense hurricanes could cause loss of billions of dollars to property. Due to drought high temperature crop yield declining, thousands of people in Africa are at risk for starvation.
In Lake Erie, climate change lower lake levels, altering shoreline habitats and costing millions for the relocation of ports and shore infrastructure. The survival of coral reefs also in endanger due to high sea temperature which generate an estimated $375 billion per year in goods and services. High temperature:
Earths average temperature rises to its highest level in last four centuries during 20th century in last thousands years it’s the fastest rise in temperature. Temperature may be increase by one degree in one area and by 12 degree in another area and yet other area becomes much colder than other.
If emission of heat trapping carbon is not reduced the average temperature of earth may increase by 3 to 14 degree Fahrenheit at the end of century. High temperatures are cause of increase in high related death, illness, rising sea level, economy loss and increased storm intensity and many of other danger ous climate consequences.
Rise in sea level due to climate change can displace millions of people. As earths average temperature increase the sea level rises because warmer water occupy more area than cold water that’s why sea level rise is threaten to coastal areas, island, erode shoreline it also damage to property or it can destroy an ecosystem. In last 100 years sea level rises between 4 to 8 inches and current projections suggest that over the next 100 years it continue to rise 4 to 36 inches. Increase in sea levels 36 inches would drench every city on the East Coast of the United States, from Miami to Boston. Increased risk of drought fires and flood:
Higher temperature increases the amount of moisture that evaporates from land and it leads to drought in many areas of world. Lands affected by drought are more vulnerable to flooding once rain falls. As temperature increases the drought becomes more frequents and are devastating consequences for agriculture & human health. The dry conditions and high temperature increases forest fires. In U.S.A melting of snow, increase in summer duration and increase in spring and summer temperature have increased forest fires.
Number of solutions to climate change has been proposed, including individual frugality, conservation of energy resource, renewable energy, and carbon sequestration Create jobs through sustainable energy system:
Climate change has been incorrectly, and successfully framed as a choice between the abstract environment and the concrete impact of the economy. United States can produce high-paying, steady employment by reducing the environmental health costs mostly associated with fossil fuel industries. Why remove a mountain for minimum quantity of coal at the high cost of people health when you can install wind turbines, protect the water, air, and land of the local community, and promote long-term job stability? Infrastructure upgrade:
Building worldwide contribute one third in emission of green house gases even though investing in thicker insulation and other cost-effective temperature regulating steps can save money in the long run. Contribution of U.S.A is 43% alone. Electric grids are at capacity or overloaded, but demands of electricity continue to increase. Stop cutting down trees:
One of major cause of climate change is forest cutting about 33 million of acres of forest cut down every year. Harvesting of Timber contribute 1.5 billion metric ton of CO2 in atmosphere. It represents 20% of human made green house gas emission. Improved practices of agriculture along with paper recycling and forest management balancing the amount of wood cut down with the amount of new trees growing could quickly eliminate this significant chunk of emissions. Consume less:
One of the easiest way to reduce the emission of green house gage to buy less stuff. Whether by renunciation an automobile or employing reusable energy resources, cutting back on consumption results in small quantity of fossil fuels being burned to extract, produce and ship products around the globe.
Employing more efficient refrigerators, air conditioners and other appliances, such as those rated highly under the U.S. Environmental Protection Agency’s Energy Star program, can reduce electric bills while something as simple as making the windows of a home weatherproofing can reduce heating and cooling bills. Such efforts can also be usefully employed at work place, whether that means installing more efficient turbines at the power plant or turning the lights or fans off when you leave the office or room. Future fuel:
Replacing fossil fuels may be the greatest challenge of the 21st century. Many contenders exist, ranging from ethanol derived from crops to hydrogen electrolyzed out of water, but all of them have some
drawbacks, too, and none are immediately available at the scale needed.