The Facts of Global Warming

There is a great deal of debate about global warming and climate change and it seems it is more political than scientific at times. This makes it hard to know the real facts when politicians get in the way of real science. It is important for all of us to understand global warming so we can make informed decisions. Is global warming man-made or just a cycle of the Earth. 

Global warming is a fact and is occurring at this time. The current debate is whether or not our global warming trend is natural, man-made or both. Learn the facts and know what to look for in future discoveries.

The Greenhouse Effect and Global Warming

The greenhouse effect that is currently causing global warming is thought to be caused by gases from man-made pollution that is trapped high in the atmosphere causing the Earth to heat up. Greenhouse gases that cause global warming are water vapor (H2O), carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and other gases, with water vapor being the most abundant and carbon dioxide the most talked about [1]. Man-made carbon dioxide is caused mainly by the burning of fossil fuels like coal and petroleum.

The carbon dioxide lets the sunlight and heat in, but does not let all of the heat escape. This is called the greenhouse effect. The greenhouse effect is like getting into a car on a hot summer day, trapped heat.

This greenhouse effect is important to life on Earth. Without the greenhouse effect, the Earth would be much colder, with the average temperature being about 0 F (-18 C) instead of the global average of 57 F (14 C). Picture this carbon dioxide and other greenhouse gases as a blanket with holes in it over the Earth, some heat escapes, but the more carbon dioxide put into the atmosphere, the fewer holes there are in the blanket thus trapping more heat. There are several reasons for global warming:

  • Increased carbon dioxide into the atmosphere causing an enhanced greenhouse effect
  • Changes in the output energy of the sun
  • Sunspot cycles
  • Slight shifts in the Earth’s orbit
  • Unknown causes

Global Warming Causes Climate Change

Global warming and climate change is not the same thing, global warming causes the climate to change. As global warming continues, the climate can become more extreme. With more extreme storms, more extreme temperatures (cold and hot), more rain in some areas and worse droughts in others. As the atmosphere warms, it can hold more moisture which can cause storms to become more severe. Hurricanes can become stronger as the oceans heat up, since the warmer the water, the stronger a hurricane can become.

Is Global Warming Occurring?

Global warming is and has been occurring for centuries, but during the past 50 years, the average temperature of the planet has increased at the fastest rate in recorded history with a global increase of 1 degree F. The National Weather Service updated the 30-year average temperatures for 1981-2010 and found that the average temperature of the US is 0.5 degrees F warmer than the 1970-2000 period [2]. If the trend continues, in 50 years there will be no more glaciers in Glacier National Park in Montana [3].

Grinnell Glaciers in Montana 1887 - 2013 / USGS

Is Global Warming Man-made or Natural?

The big debate; are humans causing the current global warming, contributing to it or have no part in global warming? Looking at a chart of temperatures over the centuries, it can be seen that the Earth’s temperature fluctuates between cold and warm periods. About 1,200 years ago, the temperatures were about the same or warmer as they are today. This was at a time the Vikings discovered Greenland. Around 400 years ago, the Earth was much cooler, a time called The Little Ice Age which corresponded to an unusually low sun spot period called the Maunder Minimum. Volcanic eruptions and weather patterns like El Nino and La Nina can also cause rapid temperature changes. 

Temperature chart during medieval warm period
Medieval warm period

Looking at the CO2 chart, you can see that in the past 650,000 years, there has never been so much carbon dioxide in the atmosphere. An undisputable fact is that carbon dioxide in the atmosphere does cause the Earth to warm and since it is a known fact that CO2 levels in the atmosphere have increased dramatically since 1950, it would seem CO2 has to have an effect on the global temperatures. [NASA] But many things in nature other than man put CO2 into the atmosphere, including volcanoes, rotting vegetation and the oceans.

The burning of the rainforests is doubly bad for global warming since the burning also increases carbon dioxide in the atmosphere and trees absorb carbon dioxide. The rainforests are called the lungs of the planet, by burning the trees; you cause more carbon dioxide released into the atmosphere and lose the benefits of all those CO2 absorbing trees.

The Intergovernmental Panel on Climate Change (IPCC) reported that “there is a greater than 90% certainty that emissions of heat-trapping gases from human activities have caused most of the increase in the globally averaged temperatures since the mid-20th century.” [IPCC] [4]

Deforestation in Indonsia
Deforestation for palm oil in Indonesia / Flickr

The Man-made or Natural Carbon Dioxide Debate

There is currently a debate about which type of carbon dioxide is causing the increase in the atmosphere. There is man-made carbon dioxide and there is natural carbon dioxide. Most scientists today believe it is the man-made carbon dioxide that is causing the global warming and there is nothing naturally that could account for such a rapid increase in the rise of carbon dioxide since 1950. Other scientists believe that CO2 increases in hot years and decreases in cooler years, making the CO2 in the atmosphere more temperature dependant than a cause for increased temperatures.

The Ice Core Debate

Many of the people who claim humans are not the cause of global warming look to ice core samples. Three ice core studies have revealed that carbon dioxide (CO2) levels started to rise after global warming has started, about 800 years after. Does this mean that the higher CO2 levels are a result of global warming and not the cause?

As the Earth warms, the oceans get warmer and the warmer the oceans get the more CO2 they release. It is thought that it takes about 800 years for the oceans to warm enough to release an immense amount of CO2 [Real Climate]. Some scientists now believe that the increased levels of carbon dioxide does not start global warming, it amplifies the global warming as the increase in CO2 continues.

Another argument is that not every global warming cycle starts out for the same reason and that this global warming cycle is starting because of the CO2. This debate continues unresolved at this time.

Noctilucent Clouds and Global Warming

Another clue could be in noctilucent clouds. These clouds are the highest clouds in our atmosphere and were never observed until 1885. At that time they were only seen over the Polar Regions but have been steadily moving south in latitude (in the northern hemisphere). During July 2011, they were seen as far south as Denver, Colorado at latitude 39.7 degrees north. Scientists think that these clouds could be proof that man-made pollution is the cause of global warming. 

Beware of the Global Warming Hype

There is scientific fact and then there is news channel hysteria. Hurricane Katrina and the Joplin tornado were not proof of global warming. These were severe storms that just happened to hit populated areas. And there is no proof that hurricanes are any stronger today than they were 100 years ago. If global warming continues, severe storms can become more prevalent. It is the real science data you need to pay attention to. And real scientists stay away from the headline grabbing hysteria that cable news thrives on. In other words, the real global warming science you should pay attention to will be dull and full of real facts.

Global Warming and You

Learn as much as you can about the real science of global warming so you can make informed decisions since this will be an important subject for many decades.

Even it if it is found out that humans are not causing or contributing to global warming and climate change, there is still no excuse for burning down the rainforests and polluting the Earth into a spinning ball of hazy trash.

Copyright © 2011 Sam Montana

[1]NOAA - List of all greenhouse gases
[2] NOAA – Updated US average temperatures
[3] USGS repeat glacier photo project
[4] IPCC 2007 report

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