Global Warming - the causes
The
Michael Medved fan site has an interesting link to one of the
key causes of Global Warming.
(Hint - it's not anthropogenic CO2)
bq. The "Kyoto Accords" canard is often plopped down as key evidence that Pres. Bush has a bad environmental record. Leaving aside the fact that most every senator said they would vote against it if it created restrictions on US industry but none on developing countries, the fact is that human pollution is a minor factor in global climate change.
The link points to an article from the USGS, the
Hawai'ian Volcano Observatory:
bq.
Global reach of volcanic gases
When we think of the negative impact that volcanoes have on people, the local geographic area of the eruption generally comes to mind. Ash, lava, and mudflows are all destructive and hazardous for people who live close to volcanoes.
bq. A less well-known product of eruptions, however, sometimes has a more widespread effect. The gases emitted by volcanoes can, under certain circumstances, affect global climate and even cause mass extinctions of flora and fauna.
bq. Sulfur dioxide (SO2) is the main gas released by volcanoes that can affect climate in the short term. Chemical reactions that occur when SO2 reaches the atmosphere produce tiny sulfuric acid droplets called “aerosol.” Very energetic eruptions push the aerosol up into the stratosphere, the layer of the atmosphere from 10 to 50 km altitude (around 32,000 to 164,000 ft), where it inhibits the sun’s energy from reaching and warming the earth’s surface.
And some examples of this? Sure:
bq. Notable eruptions in recent years appear to have affected climate. One example is the 1991 eruption of Mount Pinatubo in the Philippines, which injected nearly 20 million tons of SO2 into the stratosphere that became dispersed around the globe in about 3 weeks. The recorded effect was a 0.5 degrees C (0.9 degrees F) drop in temperature for the following two years.
bq. Remember, this small-sounding temperature decrease is a global average. Even small temperature changes can affect weather systems. The year after the eruption, the U.S. experienced its third coldest and wettest summer in 77 years, and major flooding of the Mississippi River occurred. These observations are consistent with predictions made by climate modelers of Pinatubo’s effect.
And there is more in the article. Good stuff...
Posted by DaveH at June 8, 2004 10:10 AM