Enviro Saver asked:


A common mistake made by people who have a limited understanding about global warming will often loosely refer to the problem as either climate change or global warming. While the two have much to do with each other, they are two separate things that are related to the same cause, which is carbon dioxide put into the atmosphere by human activity. Global warming is referring to the rise in the average global temperature. It is this rise in temperature that causes the climate changes being seen around the world.

It may seem like it isn’t a big deal, but this really is something people should be concerned about. Global warming has been proven to be greatly caused by the greenhouse gases, mainly carbon dioxide that people are putting into the air through their daily activities. These emissions are caused by cars, airplanes, factories, businesses, or anything else that burns fossil fuels. While there are other greenhouse gases put into the air, carbon is what makes up the largest contributor from human activities. Many don’t realize that global warming affects everyone, perhaps not in the most obvious way every day, but it does affect everyone. Global warming is what is causing the earth to warm, which, as mentioned before, causes the major climate changes that are being seen. What are some of these major climate changes and what does this have to do with people? Floods, severe hurricanes, odd weather patterns such as abnormally cold or warm winters; all of these are products of global warming.
Food and resources come from the natural world and if global warming causes severe drought (which it is in many places around the world), the crop yield will be much lower and money is lost. Not to mention that it’s less food available to people. Global warming is also what is warming the polar ice caps and drying up other fresh water resources. Life needs fresh water and without it, life tends to die.

It is something that people can change if they can take responsibility over it. It is possible to slow and stop the global warming, making the world a healthier place with the necessary resources available. It means that the burning of fossil fuels has to stop. Using energy sources that don’t require the burning of fossil fuels is what is needed. The sun and wind are both excellent examples of the tireless sources of energy available to humans. Saving water and producing less waste is also needed to reduce the carbon emissions. As more people turn to alternatives instead of burning fossil fuels, global warming could be stopped, which in turn would stop causing the major climate changes that have been the cause of such devastation in recent years.

James Nash asked:

Accelerated global warming could lead to a runaway methane global warming effect due to the release of methane currently trapped in unstable methane hydrate deposits in the arctic that could be destabilised by accelerated global warming effects.

Core samples taken from old ocean sediment layers have been used to trace back in time the climate changes that have occurred over the past tens of millions of years. By analysing the incidence of different fossil shell remains of sea creatures occurring in these sediments it is possible to track the changes in the sea water temperatures and levels of atmospheric CO2 occurring at the time the shells were formed and deposited. These shells contain carbon from the CO2 in the atmosphere which was dissolved in the sea water in which the creatures lived just as takes place today.

From these records it appears that there have been short periods of only a few hundred years in the geological past when rapid increases of the Earth’s temperature have occurred superimposed on top of the rise and fall of average temperatures over the longer term. For these short periods temperature rises of up to 8 degrees centigrade appear to have occurred on top of existing long term rises of 5 to 7 degrees to give temperatures up to 15 degrees centigrade warmer than today. Temperatures then fell back to the long term trend, the whole rise and fall only lasting a few hundred years.

The most likely cause of this rapid global warming over such a short period is the release of methane into the atmosphere. Methane is 60 times more powerful than CO2 as a greenhouse gas but only remains in the atmosphere for about ten years and so looses it’s greenhouse effect quickly compared to CO2 which remains in the atmosphere for 100 years. CO2 would not be available in sufficient quantities to achieve the rapid warming and if CO2 was the cause then the raised temperatures would last a lot longer.

Methane hydrates occur extensively today all over the world. They consist of methane stored within unstable water bound deposits that if disturbed release the methane. They occur in major river deltas such as the Amazon delta and in old delta areas such as the Gulf of Mexico. Major rivers carry millions of tons of silt containing vegetable matter that continues to decay after the silt is deposited in the river delta. This anaerobic decay produces methane which gets trapped in the silt as methane hydrates until the conditions of water temperature and pressure change which can release the methane in vast quantities very quickly.

Another form is a frozen slush/ice methane hydrate where the methane is trapped in an ice/water mixture which releases the methane when it warms up or the pressure on the ice is reduced. Frozen methane hydrates can contain 170 times their own volume of methane. These frozen hydrates occur in the seabed deposits of the Arctic Ocean.

Methane can also be trapped by permafrost layers which over-lay lower unfrozen layers of vegetable material that is decaying and producing methane which remains trapped by the frozen permafrost on top. If the permafrost layer were to melt then the methane in the layers below would escape into the atmosphere. Given the vast areas of permafrost in northern latitudes there is a significant potential for methane to be trapped that would be released if the permafrost melted as a result of global warming.

The theory for these rapid rises and falls of temperature, based on the geological records from 55 million years ago, is that gradual global warming due to some natural cause had resulted in temperatures 5 to 7 degrees centigrade higher than average (i.e. higher than today’s temperatures). At this point methane trapped in methane hydrate deposits started to be released into the atmosphere and accelerated the rate of warming. This would result in further warming releasing more methane.

As the atmosphere warmed different types of methane deposits would start to be released and so a cycle of methane release leading to increased warming leading to more methane release from other areas of methane deposits elsewhere in the world would become established as global warming effected different areas of the world.

There is an intriguing photograph of what appears to be a methane plume coming up out of the Arctic ice sheet which indicates that the phenomenon described above can occur. There have also been incidences of oil drilling inadvertently triggering large releases of methane from hydrate deposits. One theory to explain the loss of ships in the so called Bermuda triangle is that they have been engulfed in a sudden methane release which reduces the buoyancy of the sea water so that the ship sinks.

So, does methane pose a threat today? Let us review the situation. We know there are extensive methane hydrate and permafrost deposits all around the world. We have evidence that we are at the beginning of a period of global warming that is probably being made worse by the continuing build up of CO2 in the atmosphere due to fossil fuel burning. Recent computer modelling incorporating the feed back effects of global warming that has already occurred suggests that by about 2050 we may start to loose the beneficial effects of the Amazon rain forest as a carbon sink.

This could lead to temperature rises of 5 to 8 degrees centigrade by 2100. This would be uncharted territory and no one really knows at present how the world’s environmental systems would change but we now have the evidence from the geological past. On the basis of this evidence global warming can lead to methane releases which once started would escalate. This would be the worst possible thing to happen because once started there would be no way of stopping a runaway methane global warming event.

We CAN reduce our CO2 emissions from fossil fuels but we COULD NOT reduce methane emissions once they started, huge natural forces would take over and change our world. This would probably result in the melting of the Antarctic icecap which would raise sea levels by 50 metres and would completely change the climates of the world.

So what should we do? We should be careful and not risk starting the sequence events described above. To do this we must reduce total CO2 emissions from now onwards and take measures to protect carbon sinks such as the Amazon rainforest.

If we all carry on burning so much fossil fuel as we do now we will be running the risk of starting an unstoppable runaway methane global warming event within the foreseeable future. Only major absolute reductions in CO2 emissions NOW will avoid this risk.

Nathalie Fiset asked:


While the drastic effects of global warming has been discussed in many scientific circles, had their run on TV and even had major exposure through well-meaning (but sadly inaccurate) Hollywood films, it’s a concern that has a broad political, economic, social and geographical significance to countries all over the world. Quite literally, for all of us, there is nowhere to hide, nowhere to run and we can’t stop the climate from changing. It’s just way too big for us.

How to recognize global warming

Whether or not it’s brewing something good or something bad, Nature always tries to warn us through many signs. The slow process involved in global warming results in many different things and some of its signs include:

Melting of glaciers

Most of the mountain glaciers on our planet that have been monitored for the past 150 years are reportedly shrinking. The glaciers most affected by global warming those located in the lower latitudes and many of them are disappearing. If glaciers continue to shrink, it could affect water supply in areas that depend heavily upon mountain watersheds.

If the scenarios of global warming continue, most of the glaciers that still stand today will disappear by 2100.

Ocean warming

Sea level increase is attributed to warmer temperatures, which in turn result to the melting of ice glaciers. Over the last 100 years, sea level has increased from 10 cm to 25 cm. Projections over the next hundred years indicate that sea level will rise higher, from about 15 cm to 90 cm. Based on the higher figure, that’s about 3 feet.

Translated, this could mean that beaches lose about 50 feet of area for every foot of increase in sea level. Some islands may even disappear beneath sea water completely.

Heat waves

Heat waves and periods of weather that are unusually warm are also signs of global warming. These may come about with varying degrees of their severity and frequency, causing concerns in the economics and health on a global scale.

How global warming brings climate change and what it means to us

The earth’s climate has always been changing, although not at an abrupt rate. There had been periods of warming and cooling in the earth’s 4.65 billion-year history. Strange as it may sound to some, this is the reason why life became possible on this planet millions of years ago. Unfortunately, not all of the changes in climate brought about by global warming may be beneficial to many of us.

For one, global warming will raise the temperatures in some regions of the Northern Hemisphere, causing the melting of mountain glaciers. This means that areas that are currently experiencing light snow may no longer experience snowfall anymore. Snowlines found in mountains in temperate regions may also be higher and packs of snow will melt earlier than before.

Spring may be experienced earlier and temperatures during night time and in winter will rise. The world will experience a more humid atmosphere since sea water will have a higher rate of evaporation. With greater humidity, rainfall is expected to increase on average.

Storms will also occur with more frequency and intensity. Ironically, water in the soil will evaporate faster, causing dryness between rains. Regions that are already considered dry will experience more dryness. Some semi-arid regions in the African continent, for example, may suffer more while areas that depend on their region’s mountain snow packs for irrigation will not benefit from earlier melting between growing seasons.

With warmer weather, some hurricanes will be more severe and winds are expected to blow stronger. It is also possible that wind patterns may shift. Extremely cold periods may be experienced as well.

The phenomenon known as El Nino may occur in more frequency and severity. This is expected to affect different regions in many countries. All in all, scientists will have some difficulty in predicting weather patterns.

With changes in climate brought about by global warming, health concerns and risks may also increase. Heat stress and diseases may become common in places that did not have any problems with them before.

Global warming is an issue that requires immediate action. Even plants and animal species are adversely affected by it. While many of the changes that occur in our planet are totally out of our hands, we have been direct contributors to events that have had negative effects on our environment. This is why many leading social and scientific organizations have urged nations to cooperate in the move to counter this worldwide problem before it’s too late.