23 June 2011

Climate Change

You don't need to believe in climate change.  It's pretty much a done deal - no belief is necessary. It's been going on since the beginning of time, and there is a huge trove of evidence supporting the fact that our world is always changing. This evidence comes from isotopic evidence in lake bottoms, it comes from fossil evidence - warm-blooded fresh water animals whose remains have been found in Antarctica. There is even evidence from packrat middens (ancient packrat nests that can be dated using C14), and tree-rings. I have visited building sites while surveying in the southwestern US that show a huge population existed in the region that today could no longer support even a fraction of the evident population. I could fill my house with all the evidence that has been accumulating that shows our climate has changed and is changing.

What most people are hollering about these days is a slightly more specific question: how much of the recent climate change is anthropogenic - that is, human caused?  It's no surprise to anyone that we are using more fossil fuels today than are being replenished - by many orders of magnitude. Records kept since the 1950's at an atmospheric observatory on Mauna Loa volcano's north flank in Hawai'i show a steady rise in CO2 in our atmosphere. Recently, scientists have made enough measurements to quantify what is contributing to this CO2 increase in our atmosphere. A brilliant scientist who used to work for me (now retired) named Terry Gerlach recently published a paper in EOS, the weekly newsletter of the American Geophysical Union (14 June 2011 issue).

Some nay-sayers have argued that volcanoes contribute most of the CO2 to our atmosphere. Here are the final measured numbers:

Volcanoes: 0.26 Gigatons of CO2 per year
Humans:   35 Gigatons of CO2 per year

And it's accelerating: there has been a 550% increase in atmospheric CO2 emissions just since 1950. It's a known Greenhouse Gas - high-school kids prove this in physics classes.

How could this be? Well, for starts, China is bringing one new coal-fired power plant online every week.

Until recently, geologists broke up prehistory into several categories:
The Precambrian Era ended about 542 million years ago (we start seeing fossils).
The Paleozoic Era ended about 250 million years ago when ~ 95% of all living things died.
The Mesozoic Era (the age of Dinosaurs) ended about 65 million years ago when a 10-km/6-mile diameter asteroid crashed into what is now the Yucatan Peninsula.

We are now in the Cenozoic Era, which has several sub-sets:
  - The Paleocene lasted until 56 million years ago
  - The Eocene (when horses first appeared) lasted until 34 million years ago
  - The Oligocene lasted until 23 million years ago
  - The Miocene lasted until about 5 million years ago
  - The Pliocene lasted until about 1.8 million years ago
  - The Pleistocene (Saber-Tooth Cats, Mastodons, etc.) lasted until about 10,000 years ago.

Until recently, the last 10,000 years have been just called the Holocene. Now it is broken up to add a more recent epoch: the Anthropocene:  The time when Man started changing things. When mass-extinctions have accelerated so fast that it's comparable now to the extinction of the dinosaurs.

Latter-Day Saints understand that the Earth is a living thing.  Implicit with that understanding is a responsibility to take care of her.  

Abundant recent evidence suggests that politicians aren't up to doing anything about this.

But 65 million years ago, everything changed in just a few hours with the Chicxulub Event, with an explosion equivalent to about 100 million megatons of TNT.  About 30% of all life-forms were destroyed.

Are you ready for a very short-notice change?  Does the Abomination of Desolation ring a bell?

Somehow, I think that is in His Toolkit.


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