Examining Evidence Of Climate Change Environmental Sciences Essay

The definition of climate change is the change in global climate over time due to Natural and human influences. The main natural influence is the Greenhouse effect. Some scientists have come to the conclusion that the world is experiencing climate change, carbon dioxide in the atmosphere is rising, the polar icecaps are melting and sea levels are rising.

Health issues connected to climate change include Water, food and vector borne diseases, Respiratory disease, Solar radiation, Heat waves and flooding. Vector borne diseases such as Malaria and Dengue fever have increased due to climate change since 1975. Malaria is extremely sensitive to climate change, as malaria is common in warmer areas of the planet such as Africa and is sensitive to temperature changes, many studies have come to the conclusion that climate change is responsible for Vector borne disease spreading to cooler areas, the disease used to be rare in cooler areas of the world.

Variations in solar radiation are thought to effect climate change by causing the earth to get warmer due to an increase in sunspots.

Radiation will be increased due to cooling of the stratosphere which increases the effect of ozone depleting gases, also climate change alters cloud formation which can allow more radiation to the earth’s surface, and higher temperatures results in people spending more time outside increasing exposure to solar radiation. (IPCC, 2010).

Heat waves have led to many deaths particularly in the elderly especially if they suffer from other health problems as well as they cannot cope with changing temperature extremes. Heat waves also cause dehydration from loss of salt and fluid due to sweating which in turn can result in coronary thrombosis due to high blood concentration. Flooding is due to the rise in sea and river levels and more intense rainfall, there are many consequences that come from this which are loss of homes and personal belongings, productivity loss for businesses, effects on tourism, farming, interruption to Gas and electricity supplies connected to electricity loss is disruption to communication ie TV, telephones, radio’s and the internet. (Architecture.com, 2010).

Vector borne diseases such as Malaria and Dengue fever have increased due to climate change since 1975. Malaria is extremely sensitive to climate change and warmer temperatures support disease transmission resulting in a spread of the disease to cooler areas. Warming Temperature coupled with air pollution can lead to increased chances of respiratory disease such as COPD, asthma and bronchitis. There is a lot of evidence to suggest climate change is having an impact on aeroallergens, mould spores and pollen activity which is directly linked to asthma.

The greenhouse effect occurs when gases in the atmosphere mainly carbon dioxide, nitrous oxide and methane trap energy from the sun and keeps the planet at a range of temperatures to sustain Human life, without this effect the earth would be 60F colder. Manmade greenhouse effect happens when fossil fuels are burnt greenhouse gases escape into the atmosphere and enhance the natural effects. Burning fossil fuels also increases the concentration of carbon dioxide and many scientists believe this is responsible for global warming. (Weatherquestions.com, 2010)

Scientists have predicted that rising sea levels due to melting ice sheets will push up sea levels by a metre by 2100. This occurrence happens because of thermal expansion, in simple terms as sea water warms its density decreases and volume increases, the ice melts quicker than the snowfall is being replaced resulting in rising sea levels. The impact of this is flooding in low lying coastal area’s affecting 10% of the world’s population. Projections of global sea level rise by the IPCC in 2001 ranged from 9 to 88 cm by 2100. (Science Daily, 2009)

A Large percentage of scientists however have come to the conclusion that global warming does not exist, they believe that there is not enough evidence to conclude that CO2 realised into the atmosphere by man is causing the so called greenhouse effect 17,000 scientists have signed a petition to this affect. (Captitalism Magazine, 2001).

At the UN Climate summit in Copenhagen governments are attempting to reduce greenhouse gas emissions and stop human induced climate change with a new global agreement, the scientists who disagree have come up with ten reasons why we are not experiencing climate change.

Reliable sources of temperature data show no global warming trend, as all global warming predictions are done using a computer model not historical data.

It has been found by instruments that the earth is warming up but the instruments do not show true values as the readings are taken in urban areas and because of the urban heat island effect where an urban area is warmer than the surrounding rural areas the readings will not be correct.

And some areas of the world don’t even have access to instruments so overall the readings are subject to large errors. Since 1998 records show from using satellite predictions there no significant warming.

The earth was found to be warmer in the recent past, where temperatures in Europe were higher than they are now, and the arctic was warmer in 1930 than it is today. Computer models have been found to be unreliable because they cannot model all the variables that can affect the weather such variables being, influence of clouds, distribution of water vapour and warm seawater’s impact on ice shelves.

Computer models predict atmospheric behaviour but the measurements are showing the opposite so the computer models are wrong or the measurements are somehow incorrect. The sun is now thought to be responsible for climate change due to its changing output and solar wind.

CO2 rises that presumably occur before temperature rises is believed to be not the case in fact the CO2 rise happens after the temperature change suggesting that warmer temperature increases the gas escape from the oceans.

The use of satellites to establish weather trends was only started in the 1970’s so measurements where not very accurate before that time, a lot of effects such as Hurricanes and the extent of arctic ice would therefore be observed only when they could be seen. The use of satellites therefore is so short that any claims of significant increase in Hurricanes getting stronger or arctic ice sheets reducing cannot really be justified.

Water vapour is the main natural greenhouse gas that keeps the earth’s surface warm it is responsible for 98% of all warming so any rise in CO2 or methane would have a relatively small impact, and distribution of water vapour can occur in many different ways so its rise does not necessarily increase warming.

In conclusion some groups of scientists are sceptical about climate change and have some very plausible arguments against it but each and every argument can be answered by the scientists who believe it is occurring, so therefore it may come down to personal opinion until a time when there is concrete evidence for or against climate change. (BBC News, 2009).

As reliable data collection methods are relatively new accurate judgements are difficult to make on data over 30 years old.