What is Global Warming?
Atmospheric gases (primarily water vapor but also including carbon dioxide, methane, ozone, etc.) work together to retain some of the sun’s heat so that the earth stays a comfortable climate – this is known as the greenhouse effect and is necessary for human life. Climate change – long term changes in the overall climate of a particular region – can also occur naturally. The Ice Age, for example, is thought to be a natural change in the global climate. Some believe this was caused by a change in the distance between the earth and the sun, or a change in the earth’s orbital path, while others believe this climate change may have came about because of meteorites.
According to temperature records over the past 150 years, the average global temperature has risen at least one degree overall and more than 2 degrees specifically in the arctic. Scientists have also discovered a correlation between these temperatures and the level of carbon dioxide (and more recently methane gas) in the atmosphere.
Sky Factory by Taras Kalapun- In a perfect world, the trees and plants would balance the carbon dioxide levels in the air and a natural animal population would emit just the right amount of methane and CO2 to keep the atmosphere and climate in check.
In our world – we’ve removed vast amounts of vegetation to make space for structures that operate on polluting fossil fuels; we degrade land by breeding huge herds of methane-emitting cattle to feed our growing population; we manufacture products using processes that create even more gases. Our normal habits have altered the gas balance of our atmosphere, retaining more heat than ever before, and is considered to be the man made side of global warming and the current climate change.
Is Global Warming Real?
We’ve examined this question in a previous post, Global Warming: Fact or Fiction. Whether man made or natural, can anyone truly argue the fact that climates are changing around the world? Yes, global warming is real – Britain’s National Academy of Science states: “The world’s leading climate experts at the Nobel Prize-winning Intergovernmental Panel on Climate Change believe that it is greater than 90 per cent likely that human activity is responsible for most of the observed warming in recent decades. That is a pretty strong consensus.”
Global Warming Proof
"Global warming will intensify drought and it will intensify floods,” states Stephen Schneider, editor of the Climatic Change journal. 2007 brought some of the worst floods in history to a number of countries around the planet – including 14 African countries, the UK, Malaysia, the US midwest, and North Korea. Droughts and water shortages have been just as prominent in recent years – plaguing areas of the Middle East, the southeastern US, Spain, and Australia.
Extreme summer temperatures are another obvious proof that global warming is real. Not only are the summers becoming unbearable in many regions around the world – they’re lasting longer and longer. In fact, here in the Blue Ridge foothills of the southeast US, the leaves are just now showing their bright autumn colors and the highs were in the 70′s last week. 10 years ago, short sleeves were out of sight before the beginning of October!
These unusual changes in climate have also been linked to more frequent and more intense forest fires across the world. Wildfires in the past decade have burned longer, destroyed more land, and happened more often than ever before. The US, especially the southeast and southwest, have been affected drastically by these fires. Fires are also starting in forests in the Amazon, Siberia, Greece, Indonesia, and a number of other countries around the globe.
Interesting Effects on Weather
Global warming does not mean a universal and uniform warming of planet Earth, nor does it mean the end of highly unpredictable weather patterns. However, weather patterns are the result of an enormously complex process, and the effects of global warming on this process could be horrific.
There is a lot of uncertainty about how the different “feedbacks” operate, given the complexity of global weather systems. There is concern that global warming could cause changes in massive ocean currents like the Gulf Stream, which is part of a global system referred to as the oceanic “conveyor” because it propels enormous volumes of heat around the world. If this happened, it would cause huge changes in global weather patterns.
The consequences will be enormous no matter which systems are disrupted first. Scientists are unsure about which systems in the world’s climate — tropical currents versus polar currents, or events on land versus in the ocean — cause or trigger changes in other systems. Even though you may live in a relatively stable climate, at some point the ecosystem you live in is greatly affected by climates around the world.
Is Uncertainty a Cause for Doubt?
Briefly, the answer is no. While we will never comprehend all there is to be known about such a vast and interdependent system, the larger trends are clear. You should use these uncertainties as a springboard for action, not a rationalization for further, unnecessary debate.
We Must Act Soon
The most alarming danger is that once warming reaches a certain level, it could cause global climate and weather patterns to shift quickly and dangerously. We now have a fairly detailed understanding of the Earth’s climate from the last 600,000 years and more. In the past, the climate has not changed slowly, nor has it changed in a linear, incremental fashion.
Abrupt changes dramatically alter life on Earth. Sudden shifts in temperature or ocean currents result when a certain amount of pressure to change is put in place. Ocean currents like the Gulf Stream that distribute heat and moisture around the world have historically changed course in a matter of a few years, or even a few months.The historical record has shown us the devastation this sort of change can wreak on entire ecosystems.
Sources:
Marris, Emma, “Warming world altering thousands of natural systems: Analysis shows effects of climate change on almost 30,000 biological and physical phenomena,” Nature News, 14 May 2008
Eilperin, Juliet, “Climate Shift Tied To 150,000 Fatalities Most Victims Are Poor, Study Says,” Washington Post, 17 November 2005, p. A20, also published in Nature, Volume 438, Number 7066, p. 257-394
Brown, Lester, Plan B 2.0; Rescuing a Planet Under Stress and a Civilization in Trouble, Norton, NY NY, 2006, p.63
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