Repeatedly I have had questions about climate change addressed to me, both electronically in Ask-A-Geologist, and verbally from acquaintances There are a lot of things floating around in the “news media” about climate change. A lot of this is correct, some of it is foo-foo, and far too much of it is deliberate obfuscation by people who have an agenda.
Q: Is climate change real, or is this some liberal Mother Earth tree-hugger thing going on here?
A: A short summary of what’s going on:
The Knowns:
1. Virtually all climate specialists not paid by Big Oil agree that the Greenhouse Effect is real. In fact, it was first reported in the scientific literature by Joseph Fourier (of Fourier transform fame) in 1824. It’s been tested and proven repeatedly ever since. Even some large oil corporations have accepted it and are planning their futures accordingly.
2. There is a lot of yearly and decadal variability in climate data. Anyone can cherry-pick the weather data to prove any point they want to – but that’s not science. If someone is trying to convince you that climate change is not happening, ask yourself: who’s paying this guy?
3. CO2 in the Earth’s atmosphere has gone from 315 ppm in 1958 to over 400 ppm today (Mauna Loa observatory). Virtually all scientists with integrity accept that most if not all of this change is due to human activity. The reason? The change has been accelerating (second derivative is positive) since about 1850, when the industrial revolution really got underway. By second derivative being positive, I mean that it is ramping up faster and faster as time progresses. This is the well-known “hockey stick” graph made famous by Al Gore. Is it human caused? If we look at the carbon isotopes in this increased CO2, we can show that it is definitely caused by fossil fuel burning. There is less and less carbon-14, which means the new CO2 in the atmosphere is fossil carbon – from oil and coal burning.
4. The last time the atmospheric CO2 reached this level, according to the geologic record, was during the Pliocene (5.3 to 1.8 million years ago). At that time, about half of Florida was underwater (including the places where ~80% of Florida’s population now lives). I’ve personally pulled Pliocene marine fossils (sharks’ teeth and echinoderms) out of land deposits in Florida with my own hands; they are on my bookshelf.
5. There is a latency of CO2 after it gets into the atmosphere, and some scientists calculate this to be about 30 years. Translation: it tends to stay there. The oil you burn today will really be impacting your kids 30 years later.
6. A gallon of gasoline, which weighs 3 kg, will produce about 10 kg of CO2. The extra mass comes from the oxygen you might want to breathe instead. That’s less than 40 kilometers in my car. And that’s not even counting the CO2 generated to refine the gasoline. The EREI (Energy Returned on Energy Invested) for Athabascan tar sands is between 4 and 7. Translation: a rather huge amount of energy is used up just getting the bitumen into the form of gasoline.
7. Nearly 5 billion people on Earth want to have a high-protein lifestyle like their grandparents could not have even dreamed of. This means vastly-increased herds of vegetation-eating, meat-producing animals. The amount of methane a cow produces is truly breath-taking (pun intended): up to 500 liters of methane a DAY. That’s more than a 5-drawer file cabinet. Methane is 37 times more potent than CO2 as a Greenhouse Gas for capturing solar heat. That’s translates to the volume of my office in CO2 equivalent – produced in one day by one cow.
8. Increased temperatures mean more glacier calving, more melting of Arctic, Antarctic, and Greenland ice caps. Less white stuff on the ground means the darker (the light-and-heat-absorbing) under-layers will be exposed, trapping yet more solar heat and making the inevitable change non-linear. Translation: the changes will likely accelerate with time.
It’s not hard to draw some conclusions from all this:
1. Do NOT to buy beachfront property. Anywhere.
2. Move to the Pacific Northwest, or to the Canadian prairie provinces. They will be among the few winners of climate change.
The Unknowns:
There are several unresolved questions still:
1. How Fast:
How quickly will the global climate change consequences befall us? This current speed of change has never happened before, as far as geologists can tell, in all of Earth’s history. Predicting our future depends on climate modeling, and these models are fraught with assumptions and disagreements. However, they are beginning to coalesce, and are in general agreement.
2. How Bad:
Likely consequences include (but these cannot be easily quantified):
- Sealevel rise… and because of tectonic settling this will be worse on the east coast of the U.S. This means more, far-reaching devastation from storms like Katrina and Sandy are in our future.
- We can expect bigger and more devastating hurricanes and tornados. If seawater rises and hurricanes grow in average size, then the storm surges they drag with them will reach deeper and deeper into the continental interiors. A majority of humanity now lives within 100 km of a seashore.
- Greater and more terrible droughts and wildfires can be expected. Because of well-intended but ultimately catastrophic wildfire suppression policies over the past century, these fires will become truly terrible in the continental U.S., Russia, and Brazil.
- A consequence of droughts and wildfires: massive disruption in the world’s food supplies.
- We are already seeing mass extinction of animal life – and explosions of other destructive types of life (e.g., poisonous jellyfish, toxic algae). The current mass extinction of wildlife (habitat destruction and over-hunting) is comparable to what the Chicxulub asteroid did 65 millions years ago to the dinosaurs.
- We are already seeing acidification of the oceans, with consequent dissolution and destruction of coral reefs, a major host of biodiversity – and the world’s protein supply.
The gas hydrates/methane clathrates issue leads to inevitable questions about non-linearity in climate forcing – and tipping-points. In other words, can things get out of control? Is it already too late – will we see a runaway temperature rise? Will we see inundation of most of the world’s great cities (a real Waterworld)?
The geologic record says yes – it’s happened before for natural reasons – but the geologic record also shows that the Pliocene warm period came on far more slowly than what we are seeing in the modern world climate: it took hundreds of thousands of years to raise CO2 levels then – as fast as humanity has done in the past half century.
We are already in unknown territory, and precise predictions are probably not going to be correct.
~~~~~