The Mechanics of Global Warming

For years now people have been saying the words ‘global warming’ to an overall extremely mixed response. Generally, there are three types of people: Those who believe in it completely, people that don’t know enough to judge, or frankly don’t care and finally, people who are completely opposed to the idea. I am in group 1 and though I have limited sympathy with group 2, I can understand why those in group 3 have been sceptical. Overall, global warming and some of those who have tried to act upon it, has had a lot of bad press. What with rumours about scientists exaggerating data, governments and individuals alike saying one thing and then doing the other (how do all the world’s leaders get to all these environmental conferences I wonder? Polluting aeroplanes ring a bell….) and also the belief that global warming is a natural phenomenon, not caused by humanity, its no wonder people have doubts. Perhaps I may be coming across as biased, but I believe it is past time for people to realise that global warming is happening, natural or not, and we, as humans, need to stop making excuses like ‘its natural’ or ‘it’s too late to act now’. There are no longer any excuses that are reasonable enough to convince me and many others that global warming is not occurring which is why we need to be acting now, not later, now. Now I don’t want this blog to turn into an argument, but I have always been keen to convince people that global warming is a human induced phenomenon, so I will discuss some information that I believe supports these claims.

Before I do so, however, during my research for this article, I encountered a quote which I believe sums up the issues that circulate around the argument for global warming: ‘There is a great incentive for people with political or environmental causes to warp the data in a desired direction.’

The Hockey Stick Debate

The changes in global temperature we have been experiencing in the past century have been really quite unique and unlike anything we have seen before. The hockey stick debate, I believe, is one the best evidence to use for global warming – again, this is a very controversial piece of information that has been much disputed, I do, however, believe that it is very important.

The Hockey Stick debate (diagram from Google Images)

As we can see from the diagram above, studies of temperatures over the past 1000 year have produced a fairly constant pattern of earth’s natural increases and decreases in temperature, but, as we approach the 1800s and 1900s, the time of the industrial revolution, we can see a steady increase in temperatures as industrialisation results in increased greenhouse gas emissions that cause global warming (this will be explained below). Now, personally, I believe that it is too coincidental for this rapid increase in temperatures to have occurred at the same time that greenhouse gas emissions increased so rapidly, suggesting that global warming is human induced.

How does global warming work?

When you believe in that explanation or not – I should make it clear that the example I have used is just one of many pieces of evidence that suggests that global warming is occurring because of humans – it cannot be denied that the global climate is strongly influenced by the presence of greenhouse gases in the atmosphere. Greenhouse gases in the atmosphere are actually a necessity to keep the planet consistently warm. If we study the diagram below, we can see that solar radiation from the sun enters the atmosphere – some of this radiation is then absorbed by the earth, keeping it warm, whereas the rest is either reflected back into space or absorbed and then re-emitted by greenhouse gas molecules which results in further warming of the atmosphere. As mentioned, this is a natural process that is needed to keep the earth warm. That said, however, if there is too much greenhouse gas in the atmosphere – caused by human activities that release greenhouse gases – too much radiation is then absorbed and re-emitted by the gases making the planet unnaturally and dangerously warm. Even an increase by 1°C could be disastrous for the planet and considering that the temperatures we are now witnessing are the hottest we have seen in 800,000 years, we have plenty of cause for concern.

Greenhouse effect (map/graphic/illustration)

Greenhouse effect (diagram from Google images)

What causes global warming?

Global warming is caused by human activities – we are responsible for emitting huge levels of greenhouse gases into the atmosphere through our production of power, our transport, our industry – basically, our burning of fossil fuels. As  explained above, these increased levels of greenhouse gases cause accelerated warming of the planet which causes huge issues for life on earth as we know it.

What impacts is global warming having on our earth and what will it do in the future?

The effects global warming has on the earth are numerous and extensive. I don’t intend to list all of the effects here – we don’t actually know all of the potential effects it could have, as yet – but I will list some of the main ones. Perhaps one of the biggest issues that is being caused, and will be worse in the future, is the melting of the polar ice caps. The volumes of ice in the Arctic and Antarctica are huge – some of the ice in Antarctica, for example, is in places a mile thick. That said, however, temperatures in Antarctica remain on average around -37°C, suffice to say, still very cold but in the Arctic circle, there is already extensive evidence of melting. There are also various other issues with places like Greenland that also has a lot of ice at risk of melt and it is more at risk because of its proximity to the equator – closer proximity, at least, in relation to the poles.

As the freshwater icecaps melt, they cause global sea levels to increase which will result in low-land and coastal areas across the world becoming flooded. If all of the ice in Antarctica were to melt, the sea would rise as much as 200feet whereas if all the ice in Greenland were to melt, sea levels would rise as, much as 20feet. Areas that are likely to be flooded in such an event range from islands, countries and to some of our largest coastal cities it is estimated that 60% of our world’s population live in coastal areas that are potentially at risk from flooding. To list but a few examples: Indonesia is a low-lying country and thus could be almost totally submerged, as is Bangladesh; large cities in America on the coast such as Los Angeles and New York are also at risk. As is our capital, London, not only because of sea level rise but also because of isostatic movement. (See information below) and many islands such as the Maldives could also be lost. Overall, flooding will cause numerous problems as people will be forced to leave their homes and settle elsewhere where they may not be welcome and in LEDCs it may exaggerate problems with poverty; the abundance of standing water, for example, would be ideal for the breeding of mosquitoes and other insects which will cause diseases like Malaria to spread much more easily. Also, farmland, which we have too little of to sustain our growing population and is already at risk because of climate change, is often located at low elevations and when land is flooded by saltwater, crops are ruined and soil becomes saline and thus essentially useless for further growing…. I could go on.

Melting Polar Ice caps (Photo from Google images)

Isostatic movement involves the weight of ice and glaciers. The sheer weight of ice during glacial periods compresses the land causing it to ‘sink’. When these glaciers melt, however, this extreme weight on the land is lost and thus the land is able to rise again slowly. The last place in the UK to have glaciers was Scotland and it is still rising from its last glacial period. If you imagine Britain is like a boat on the sea, if one end of the boat rises, the other end of the boat sinks until eventually it balances itself out. As Scotland is rising, southern England is sinking gradually, so a combination of rising sea levels and isostatic movement could cause places like London as well as other areas in the South to flood extensively.

The melting of the polar ice caps will also cause many other problems; the mixing of freshwater with saltwater is thought to be a potential risk to important currents that circulate both warm and cold waters across the globe. The most important change for Britain is any change that could occur to the Gulf Stream, a stream of warm water that bathes the UK and North-west Europe in warm water from the Caribbean. This stream of warm water makes our seas warmer and thus makes the landmass warmer – it is allows the Norwegians to grow strawberries along their coastline, palms to grow in Cornwall and it keeps the UK and North-west Europe 5°C warmer and prevents us from having fierce and bitter winters. The slowing of the stream has been linked to dramatic regional cooling in the past – the current was weakened 10,000 years ago causing European temperatures to fall as much as 10°C. Models are now predicting future weakening in the Gulf stream as a result of the large-scale melting of ice – freshwater – into the North Atlantic – saltwater (it’s all to do with the densities of the water and how they vary between saltwater and freshwater.) Studies show that the cooling and freshening of the Norwegian Sea may be linked to the already falling temperatures in parts of the region as a result of an already weakened Gulf Stream – so our typical idea of a more Mediterranean climate when we think of global warming, is not actually correct.

Global warming will cause huge changes to the world’s climate as we know it in ways that we may not understand or expect – I myself was surprised by the idea that a weakened gulf stream would result in places getting cooler as opposed to the typical idea of places getting hotter. This is only one example, however, and there are several other potential climatic changes that could occur. Global warming is thought to create greater extremes of weather conditions – this includes things such as hurricanes.

Hurricane formation is extremely dependent on oceans warmed up to 27°C as the oceans provide the heat that fuels the hurricane. If the oceans are warmer because of global warming, more storms and hurricanes will occur and they will be significantly more powerful. New studies have shown that hurricanes and typhoons alike have become 50% stronger and have lasted for longer over the past 30 years and this correlates with a rise in sea surface temperature.

Hurricane Katrina (Photo from Google images)

As well as hurricanes, there are many other examples of extremes of climate that may occur and seem to have been occurring in recent years because of global warming. As touched upon in a past article (http://mondeenvironmental.wordpress.com/2011/06/28/barn-owl-populations-in-decline/) extremes in climate can occur because of the Rossby Waves. Rossby Waves are basically meanders in the jet stream that occur naturally but it is thought that these meanders could be greatly exaggerated by global warming. The direction of a meander dictates the type of weather received in a particular area e.g. if a meander moves south over Britain, for example, it will bring with it cold polar air and will cause Britain to experience heavy snow and extremely low temperatures. A meander that moves north, however, will bring much warmer tropical air with anti-cyclonic conditions with little rain, heatwaves and even drought. It is believed that the meanders in the Rossby waves are responsible for the extremely cold winters we have experienced over the past couple of years and it may also be the cause of our summer weather which has been extremely inconstant, even for Britain, and has involved extremes of weather. In April, for example, we received extremely hot weather that was very uncharacteristic of British spring weather and it resulted in extensive drought across much of Britain but particularly in the south. We then received a period of heavy rain and more recently, thunder and lightning – again, these are all extremes of weather uncharacteristic for Britain which rarely has weather extremes because of its location on the edge of a continent, the fact that its an island and is affected by 5 air masses and because it is in the northern hemisphere.

These are but a handful of effects that global warming will have on life as we know it. I would love to list every single potential consequence, but that would be too much for a blog and more towards an essay. These climatic conditions mentioned, are also a threat to our global wildlife. All organisms are adapted to their particular climate and ecosystems are surprisingly delicate. The extinction of one organism can cause the collapse of an entire ecosystem as it upsets the food chain and the organisms potentially dependent on that organism. If extremes of climate, such as extreme cold, kill off a particular plant, for example, any herbivores that eat that plant, may be dependent on it. without that plant, those herbivores will die and potentially become extinct. Without those herbivores to feed upon, predators may die and so the chain continues. The importance of every organism in an ecosystem can be seen in another article I have written (http://mondeenvironmental.wordpress.com/2011/06/23/the-plight-of-the-bumblebee/). So climatic changes could cause the loss of whole ecosystems – we always hear about the decline of polar bears and similar iconic mammals but the reality is, global warming will have a much greater impact on the world’s wildlife beyond the North and south poles; I am not by any means saying that the polar bear is any less important, but it is not the only organism at threat – it is simply the only one that always comes to mind.

At the same time, global warming can cause certain organisms to thrive in the new climate. A good example of this is the Whitebark pinebeetle found in the USA. The Whitepark pine is the main pine tree found at high elevations in Yellowstone. It is regarded as a keystone species and it provides both food and shelter for wildlife as well as shading snowpack to extend snowmelt flows in the summer months. The nuts of the whitebark pine are a key food source for grizzly bears and they attract the bears to the high-elevation areas of the trees, away from people. Winter temperatures have been considerably warmer in Yellowstone as a result of global warming and thus the beetles have not been killed off as they would have been by harsh winters. This has resulted in a beetle epidemic which is killing trees across the Rocky Mountain region and has taken its toll on the whitebark trees. A recent study in 2009 found that 85% of whitebark pine in Yellowstone are dead or dying and predictions say that the whitebark will be gone in a decade. Not only is this the loss of an important organism on which others depend, but it is also having an impact on humans. Hungry bears are going to lower elevations in search of an alternative food which is causing conflict between man and bear. The loss of these forests also leaves the surrounding countryside more vulnerable to avalanches and heavy spring runoff. The Whitebark Pine has now been named an Endangered species.

Dead and Dying Whitebark Pine trees (Photo from Google images)

Human induced global warming is thought to be causing more problems for the global climate. A good example of this to use is permafrost. Permafrost is permanently frozen ground that contains large volumes of carbon from plant material that was frozen in soil during the last glacial period and it is beginning to thaw in high latitudes because of increasing global temperatures. This will greatly accelerate global warming and take it partially out of our hands to manage as that carbon can only be stored if permafrost remains frozen. Many studies have suggested this, but the leader of the study by the University of Colorado Boulder’s Cooperative Institute for Research in Environmental Sciences, Kevin Schaefer, commented: ‘If we want to hit a target carbon dioxide concentration, then we have to reduce fossil fuel emissions that much lower than previously thought to account for this additional carbon from the permafrost’ He also used the analogy: ‘As long as it stays frozen, it stays stable for many years,” he said. “But if you take it out of the freezer it will thaw out and decay.’

Carbon has already began to escape because of rising global temperatures in both Alaska and Siberia and Using data from all climate simulations, the team estimated that about 30 to 60 percent of Earth’s permafrost will disappear by 2200. The study took into account all of the permanently frozen ground at high latitudes around the globe.

By listing all of these potential effects that global warming will have and the effects we can already see or almost taste, I have tried to give you, the reader, an idea of the scale of the impacts of global warming. As I have mentioned, I could go on and on with effects that global warming will have – it is such a serious problem and effects so many things, it is hard to take in the sheer scale of it but I hope I have at least provided an insight as to how immense this issue is.

What can you do to help?

Overall, the key thing to consider with minimising the effects of global warming is reducing your carbon footprint. There are various ways you can do this:

  • Use less electricity around the house; (the production of power usually involves burning fossil fuels in power stations) turn of lights that don’t need to be on, don’t leave appliances on standby, use eco-friendly lightbulbs, if your not using something – turn it off! As opposed to turning up the heating – even if it is gas powered! – put on a jumper. Set yourself restrictions on how long you spend in the shower – heating water uses a lot of energy. Have baths less frequently…the list goes on.
  • Where possible, take public transport as opposed to driving. Avoid buying large and polluting vehicles – especially if such vehicles are only ever going to be driven with 1 person in the car. (Sorry…but range rovers and the like are obscene)

Range Rover (Photo from Google Images)

  • Recycle everything as far as possible. Compost your kitchen waste, recycle as much plastic, cardboard, glass and tin, as you can. Producing such products involves using valuable resources – plastic comes from oil, for example, a non-renewable resource that is running out, cardboard comes from trees that tend to be coniferous and reduce biodiversity. As well as this, continually producing such goods uses a lot of energy and it is more sustainable to recycle everything than produce more and have our waste taking up space in a landfill… This point refers more to minimising pollution as opposed to solely global warming but nevertheless, it is just as important.
  • Consider – if you can afford them – solar panels, wind turbines, to power your own home.
  • When you travel abroad, consider your carbon footprint. Flying abroad regularly, for example, is not environmentally friendly as planes produce a lot of emissions. Consider less polluting methods.
  • Make other people aware of the issue of global warming and what they can do to reduce their carbon footprint – the more people know, the more emissions can be reduced.
  • Consider where the products you buy come from – particularly food products. Look at labels for the country of origin and, where possible, favour British products or those closer to home (I will be writing a peice on this)

These are just a handful of suggestions and I hope they will be helpful to anyone keen to reduce their carbon footprint.

Interesting links: http://ecoflight.info/issues.html

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One thought on “The Mechanics of Global Warming

  1. Pingback: The Struggling Servant of Mother Nature | Stories of My Wandering Feet & Mind

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