If you are a regular reader of The GeoChristian, you know that I lean towards the validity of anthropogenic global warming (AGW), which is the idea that human activities are causing the Earth to become warmer. Much of the debate–on both sides–is driven by ideology more than science, but I have found the scientific arguments on the AGW side to be stronger.
The AGW proponents say that variations in greenhouse gases, such as carbon dioxide, are the primary drivers of climate change at the present time. They acknowledge that the Earth’s climate naturally varies, and that greenhouse gases are not the only factors in climate change, but warn that the present changes in climate are outside of the natural range.
The Earth is an incredibly complex planet, and it is difficult to integrate all of the factors that go into something as complex as weather and climate. The issues involved include greenhouse gases, variations in the intensity of solar radiation; cosmic rays, ground cover, ocean circulation patterns, orbital variations, and others. Despite decades of intense research, it is still not possible to say with certain how much of the Earth’s natural greenhouse warming comes from the various greenhouse gases present, such as carbon dioxide, water vapor, and methane. (Don’t forget that the greenhouse effect itself is an extremely good thing; Earth would be about 30°C (50°F) colder without it).
The London Times has an article on the influence of solar activity and cosmic rays on climate: An experiment that hints we are wrong on climate change. The article examines recent experimental evidence that indicates that observed fluctuations in climate, both now and in the past, have been the result more of changes in solar output than greenhouse gases.
AGW advocates would say that we cannot wait for a couple more decades of research in order to take action. Overall, I agree, because many of the actions they say we must take are good whether AGW is true or not. Examples include increasing energy efficiency, simplifying our consumptive lifestyles, and developing sustainable, renewable energy alternatives.
Grace and Peace