
Advantages: Its a big problem with small solutions that could help IF EVERYONE did something
Disadvantages: inevitable its not going to work out, the earth will suffer and so will future generations
Let me start of from basics. Climate refers to the temperature over a long period of time, and climate change in general (this topic) refers to changes in the earth's climate - (over decades/millions of years) Climate includes the average temperature, amount of precipitation, days of sunlight, and other variables that might be measured at any given site. Weather is different as its the day to day state of the atmosphere and changes and varies all the time. (whereas climate can be predictable)
----external causes of climate change-----
Variations in solar radiation, the Earth's orbit, deforestation, ozone depletion (decrease in amount of earth's ozone) and greenhouse gas concentrations
---The Greenhouse Effect-----
(This was actually a question is the June 2007 A2 biology paper so I should be able to discuss this!)
The greenhouse effect is caused by a blanket of chemicals that surround the earth's atmosphere and prevent heat rays escaping. - The Sun's heat rays will enter and reflect of the earths surface and escape the earths atmosphere (some bouncing back - keeping the earth warm) however this cloud of gasses cause an insulation (like that of a greenhouse) so the overall temperature of the earth increases due to heat being trapped in the earth.
Greenhouse gasses are thought to be the primary cause of global warming (overall increase in the earths temperature (climate change))
the atmospheric concentration of CO2 in 2005 was 379ppm3 compared to pre-industrial levels of 280ppm3 (so theres an obvious increase due to man's intervention)
---the science behind Co2 in the oceans-----
Le Chatelier's principle explain the characteristics of the dynamic equilibrium of a gas in solution such as the vast amount of C02 held in solution in the world's oceans moving into and returning from the atmosphere. These principals can be observed as bubbles which rise in a pot of water heated on a stove
---The sun-----
The sun has its own cycles such as the solar cylce, which could be causes of climate change, however solar cycles are not yet fully understood as the changes that are occurring in the sun are over very long periods of time (Slow)
Changes in the earth's orbit change sun light intensities on the earth. The 'orbit changes' are known as Milankovitch cycles, these orbital cycles are predictable (mutual interactions of the Earth, its moon, and the other planets) - the milankovitch cycles are thought to be causing glacial changes.
---Volcanoes---
Volcanoes are more influential then you might think, a single eruption causes climate change - causes cooling for a period of a few years. So a much larger volcano eruption (occur only a few times every hundred million years,) but can reshape climate for millions of years and cause mass extinctions!
How the volcanoes cause cooling - its thought that the dust thrown from eruptions cause a cooling blanket by blocking the sun's rays, however dust usually settles within six months!
Volcanoes and Co2
Volcanoes release massive amounts of CO2 from the earth (that are usually stored (sedimentary rocks)etc). However The US Geological Survey estimates that human activities generate more than 130 times the amount of carbon dioxide emitted by volcanoes!
The biggest cause of climate change is the increase in CO2 levels due to emissions from fossil fuel combustion, followed by aerosols (particulate matter in the atmosphere) which exerts a cooling effect and cement manufacture. Other factors, including land use, ozone depletion, animal agriculture and deforestation also impact climate.
Fossil fuels have caused increases in CO2 levels from a concentration of ~280 ppm to more than 380 ppm today. These increases are projected to reach more than 560 ppm before the end of the 21st century. It is known that carbon dioxide levels are substantially higher now than at any time in the last 800,000 years!!
Like with all theories there are arguments, people believe that global warming is due to nature more than man's intervention, blaming solar activity, ocean currents, cosmic rays and unknown natural causes (e.g. Leroux)
---so what can we do about it-----
--Kyoto Protocol----
The Kyoto protocol is the most prominent international agreement on climate change, and is also highly controversial. Some argue that it goes too far or not nearly far enough in restricting emissions of greenhouse gases. Another area of controversy is the fact that India and China, the world's two most populous countries, both ratified the protocol but are not required to reduce carbon emissions under the present agreement. Furthermore, it has also been argued that it would cause more damage to the economy of the U.S. than to those of other countries, thus providing an unfair economic advantage to some countries. (people believe that production would move to those countries (as they have the major energy sources) however India and China are probably the least energy efficient countries!.
-----Explaining renewable and non renewable sources of energy----
Renewable sources of energy include the sun, the wind, ocean currents, biofuel etc.
They are renewable because they dont run out, they can be re-used again and again and are not 'wasted once'.
So why dont we use these sources to produce energy? why do we use non renewable energy sources like fossil fuels (coal, oil & gas) which cannot be replenished and cause environmental damage and have limited supply?
Its because:
1) equipment - like wind farms and solar panels cost too much - the setup costs are too great to benefit.
2) less energy produced by these renewable methods and they take more time to be produced. Fossil fuels cause a great amount of energy to be produced quickly.
Nuclear Power - provides great amount of energy and is thought to be environmentally clean, - France used nuclear power and reported the cleanest air of any industrialised country (2007 programme 60 minutes)
Why not nuclear then?
Its Uneconomical and is a potentially dangerous energy source with a limited fuel supply, especially compared to renewable energy
Also a problem of storing radioactive waste, the potential for possibly severe radioactive contamination by accident or sabotage, and the possibility of nuclear proliferation. (however new technologies claim they can safely store the radioactive waste)
So here is a summary of the causes-----------------
Man Made: Carbon dioxide · Climate sensitivity · Deforestation · Global dimming · Global warming potential · Greenhouse effect · Greenhouse gases · Keeling Curve · Urban heat island
Natural: Cloud forcing · Glaciation · Global cooling · Ocean variability · Orbital variations · Plate tectonics · Radiative forcing · Solar variation · Volcanism
The effects-------------
Sea level rise · Glacier retreat · Climate change and agriculture · National Assessment on Climate Change · Economics of global warming · Shutdown of thermohaline circulation
Mitigation's------
Individual and political action on climate change
Kyoto Protocol: Clean Development Mechanism
Schemes: Emissions trading · Personal carbon trading · Carbon tax · Carbon offsets · Carbon dioxide sink (Carbon sequestration)
Energy conservation: Efficient energy use · Renewable energy · Renewable energy development · Soft energy path
----What Can We Do Now----
We leave the politics to the politicians and we go for individual action, we can make a big difference if ALL of us take small steps and change our lifestyles
There are so many ways for example:
- in shopping ; buy energy efficient products
- use public transport instead of cars
- protecting forests, and plant new trees
- Use appliances with energy stars
- have a car with high petrol milage
- Use less animal products (rearing livestock contributes more greenhouse gases than all fossil fuel burning combined according to The United Nations' Food and Agriculture Organization )
Want more info visit http://www.campaign-green.co.uk/
Summary: This is a global problem and needs everybody to take it seriously CO2 emissions can be lowered !