Archive for February, 2009

New Estimates on Temperature Increase this Century

Monday, February 23rd, 2009

Temperature increase last century was 0.6°C. Most climatologists would like to see temperature increase this century stay below 1.4°C, and many would like to see a cap of 1.2°C or less.

A recent MIT study looks at the odds of this. FIrst, the no-policy scenario:
No-policy case
No-policy case

Without a policy, it is highly probable that we will see a temperature increase larger than that needed to throw us into a glacial period—about 4 – 6°C separates glacial (ice age) and interglacial period. A temperature increase of about this much is expected to change the climate dramatically.

With a policy, chances are better.
policy case
policy case
While the warming is still more than climatologists would like to see, there is a 90% chance of staying below 3°C this century, compared to the no-policy case, where the chances are only 1%.

The predicted increases are greater than predictions from 2002:

The differences are greatest for the reference or “no policy” wheels. In the previous wheel the likelihood of exceeding 5°C was about 4%, but in the new wheels that likelihood is 57%. There is no single revision that is responsible for this change. In our more recent global model simulations, the ocean heat-uptake is slower than previously estimated, the ocean uptake of carbon is weaker, feedbacks from the land system as temperature rises are stronger, cumulative emissions of greenhouse gases over the century are higher, and offsetting cooling from aerosol emissions is lower. No one of these effects is very strong on its own, and even adding each separately together would not fully explain the higher temperatures. Rather than interacting additively, these different affects appear to interact multiplicatively, with feedbacks among the contributing factors, leading to the surprisingly large increase in the chance of much higher temperatures.

Climate Change Worst Case Scenarios: Not Worst Enough

Sunday, February 15th, 2009

from a AAAS blog post: Climate Change Worst Case Scenarios: Not Worst Enough

• We’re increasing greenhouses gases 3 x faster than the worst case prediction. During the 1990s, GHG emissions were increasing 0.9%/year. From 2000-2007, the increase averaged 3.5%/year. This is mostly due to economic growth, mostly in China. However, new coal plants are being built in the EU (think Germany) and US, and China’s per capita GHG emissions are still lower than in the EU.

world greenhouse gas emissions
world greenhouse gas emissions—Note increase from 2000 to 2004 is equal to that from 1990 to 2000.

Changing US emissions
Changing US emissions

Even as sea level stopped rising from thermal expansion (think mercury in a thermometer), sea level increase between 1993 and 2008 was twice as rapid as in the 1960s, due to more glacier and ice sheet melt.

From another post, Fisheries Worldwide Threatened by Climate Change:

Many commercial fish stocks will likely shift their distributions dramatically as species respond to changes in ocean climate over the next 4 decades… The changing ranges could mean major disruptions to fisheries, with some nations seeing major boosts in yields and other countries–predominantly in the tropics–being the losers. Dozens of species that are unable to adapt will likely go extinct…

The Canadian fishing industry will likewise benefit at the expense of their counterparts in the United States, where cod populations may fall by 50% by 2050. Overall, climate change may cause the continental United States to lose more than 15% of its potential catch by 2050.

Indonesia will also lose out, Norway will benefit, polar species are likely to go extinct.

On the other hand, better marine management has led to healthier Hawaiian coral, and a return to higher haddock stocks in the northeastern US.

Soy is replacing rainforest, and if the US actually does produce 57 billion liters of corn-based ethanol in 2022, Brazil will plant up to a million more acres of soy, producing GHG emissions 130-650 times as much as was saved with the ethanol.

disappearing rain forest
disappearing rain forest

Recent climate change news

Sunday, February 8th, 2009

It’s been a pretty gloomy month for climate change news.

Steven Chu, Secretary of Energy, said, “I don’t think the American public has gripped in its gut what could happen…[We’re] looking at a scenario where there’s no more agriculture in California.” And, he added, “I don’t actually see how they can keep their cities going” either.

Antarctica is warming. Not a surprise, it’s just warming more slowly than elsewhere.

Tree mortality in the western US has doubled in recent years, along with the increased temperature and decreased water. (Science, subscription needed)

Ocean dead zones, now less than 2% of the oceans, transient and reversible, could increase to 20% by 2100, and last for many thousands of years.

Oceans are not all the same height, with the Atlantic side of the Panama Canal 20 cm (8 in) lower than the Pacific, and more dramatic differences elsewhere. The differences are caused by a difference in density, and currents and winds. El Nino can change sea level by 0.6 m (2 ft). So we might expect uneven consequences from increase in sea level.

Sea level rise from the melting of the West Antarctic Ice Sheet is expected to average 5 meters, 16.5 feet. But there is so much ice in Antarctica, sea level nearby is higher because of gravitational attraction, so melting will produce a smaller increase locally. Additionally, shifting all that water from the poles will change the location of the south pole for rotation by 100 m (300 ft), which will shift how the oceans are distributed. The net result is that DC and much of the US will see an increase nearer 6.3 m (21 ft) (Science, subscription needed), and South America will see less.

The emperor penguin is likely to go extinct by 2100 or a bit later.
emperor penguin
Emperor penguins mate later, likely because of climate change.

Fire in Australia, drought in China.

It’s hard to keep an intellectual distance when so much bad information arrives at once.

Why Carbon Capture and Storage?

Sunday, February 8th, 2009

I’ve been hearing from both pro- and anti-nuclear power people, NO!! to coal or natural gas with carbon capture and storage. They see a fossil fuel free world.

So why are all major policy analysts including CCS as important means of reducing greenhouse gases? Here are some answers, in no particular order:

• retrofit all the fossil fuel plants in the world (I’ve read the goal is to close all that can’t be retrofitted, by 2030?)
• capture and store industry-produced CO2 not related to electricity, it’s a lot
• fossil fuel plants, even coal, can be ramped up and down faster than nuclear for wind and solar backup. Yes, some utilities use coal to backup wind.
• nuclear buildup will necessarily be slow because it requires ability and i dotting and t crossing. Once sufficient testing of CCS has been done, anyone can make and lay pipes
• CCS with biopower is GHG negative. Today, more or less, whatever CO2 plants take out of the atmosphere while growing is returned when plants are burned (well, except for overhead for farming and transporting the fuel). With CCS, much of the CO2 absorbed during growing can go into long term storage. It is clear we need to rid the atmosphere of significant amounts of GHG.

Testing has to be done, laws made (eg, what liability does a company have?) Someone asked that question in a lecture, and we were told that originally people were thinking of a Price-Anderson type act, because that makes industry responsible, but that act is SOOO misinterpreted among members of the public that people are trying to find another solution. Translation: environmentalists have been pushing the idea that Price-Anderson is a nuclear subsidy, even though government has never shelled out a cent.