Saturday round-up: Cutting emissions, teacup by teacup

Heavily CO2 emitting coal-fired power stations like these are likely to supply the electricity to use to boil your kettle. And like your kettle, those power stations produce steam, which are the clouds shown here, not CO2 or smoke. Credit: Imperial College.

Heavily CO2 emitting coal-fired power stations like these are likely to supply the electricity to boil your kettle. And like your kettle, those power stations produce steam, which are the clouds shown here, not CO2 or smoke. Credit: Imperial College.

Your kettle and the milk you put in your hot drink are actually both powerful weapons with which to slash greenhouse gas emissions, research has underlined this week. For example, the energy the kettle uses could produce up to 60% more greenhouse gas emissions than governments have been assuming, claims Imperial College’s Adam Hawkes. “This means any reduction we make in our electricity use could have a bigger impact on the amount of carbon dioxide emitted by power stations than previously thought,” Hawkes explained. “However, this also acts in reverse: a small increase in the amount of electricity we use could mean a larger increase in emissions than we previously thought, so we need to make sure we do everything we can to reduce our electricity use.”

Hawkes studied emissions in the UK from 2002 to 2009, where the government estimates that CO2 emissions are 0.43 kilograms per kilowatt hour. That figure comes from averaging the amount of emissions produced by each different type of power source, a method commonly adopted across the world. However this ignores the fact that in the UK sudden changes in electricity demand are mainly met by coal-fired power stations, which produce lots of CO2. “A change in demand does not act upon all elements of the electricity system proportionally,” Hawkes wrote in a paper published in the journal Energy Policy last Tuesday. Read the rest of this entry »

Overheating lizards raise climate alarm

The cool mountain habitats where many of the Sceloporus lizards are found have been subjected to very rapid climate warming, resulting in the local extinction of many species, including Sceloporus mucronatus (pictured here: a pregnant female). These are live-bearing lizards that evolved very low body temperatures for these cool environments and this low body temperature makes them extremely susceptible to extinction from climate warming. Credit: Barry Sinervo

The cool mountain habitats where many of the Sceloporus lizards are found have been subjected to very rapid climate warming, resulting in the local extinction of many species, including Sceloporus mucronatus (pictured here: a pregnant female). These are live-bearing lizards that evolved very low body temperatures for these cool environments and this low body temperature makes them extremely susceptible to extinction from climate warming. Credit: Barry Sinervo

Climate change is wiping out whole communities of lizards across the world and other animals are likely to follow suit, and may already be suffering. That’s according to Barry Sinervo of the University of California, Santa Cruz, who has studied lizard populations as part of an international scientific team. “Averaged across the planet, life has become intolerably hot for 5% of the world’s populations of lizards since 1975,” Sinervo told Simple Climate. “This has pushed these populations to extinction. The global level of lizard extinctions is very scary.”

Sinervo explains that all animals have developed temperature limits as a result of millions of years of evolution. Temperatures are currently changing too fast for animals to evolve and adapt to them. “All animals are susceptible,” he explained. “It is just easier for us to prove these thermal effects in lizards because a generation of ecologists have developed the methods we used.” Sinervo points out that frogs, toads and other amphibians are currently “at huge risk” of extinction, in part due to a fungus that is affecting them. “However, even the spread of the fungus is linked to climate warming by some authors,” the biologist notes. Read the rest of this entry »

Running the numbers

Continued growth in CO2 emissions could lead to dangerous global temperature rises. The red lines represent a "business as usual" scenario that we might already be following, while the blue lines are what is needed to keep emissions below the dangerous 2°C level. Credit M. Meinshausen

Continued growth in CO2 emissions could lead to dangerous global temperature rises. The red lines represent a “business as usual” scenario that we might already be following, while the blue lines are what is needed to keep emissions below the dangerous 2°C level. Credit M. Meinshausen

In 2008, 2010 humans across the world were responsible for emitting greenhouse gases equivalent to 46 37 billion tonnes per year of CO2. In that year there were 6.7 6.9 billion humans on the planet. On average, each human on the planet was therefore responsible for the equivalent of 6.9 5.3 tonnes of emissions. Joeri Rogelj, who spoke to Simple Climate last week, suggests that by 2020 emissions should not exceed the equivalent of 44 billion tonnes per year of CO2. By that time the UN anticipates the world population reaching 7.6 billion, in its medium-growth level prediction scenario. This would mean a cut in emissions to of 5.8 tonnes per person.

The Kyoto protocol and subsequent negotiations have focussed on 1990 as the base year from which to reduce emissions. Rogelj and his colleagues estimate that in that year greenhouse gases equivalent to 36 billion tonnes of CO2 were emitted. Until shortly before the end of the negotiations for the Copenhagen Accord in December, the draft agreement still contained targets specifying a global reduction of 50% below 1990 emissions levels by 2050. This would amount to just 18 billion tonnes of CO2 emissions annually. These kind of targets are seen as necessary for keeping global temperature rises below the 2°C level beyond which climate change would be dangerous. In 2050, the UN’s medium population growth scenario predicts 9 billion people on the planet, meaning that average emissions per person would be just 2 tonnes per year. Read the rest of this entry »

Lots of shoes make for big carbon feet

China is by far the largest "exporter" of carbon dioxide emissions, as seen in this map of the net flow of emissions embodied in trade among the major exporting and importing countries. Arrows indicate direction and magnitude of flow; numbers are megatons (millions of tons). Credit: Steven Davis/Carnegie Institution for Science

China is by far the largest “exporter” of carbon dioxide emissions, as seen in this map of the net flow of emissions embodied in trade among the major exporting and importing countries. Arrows indicate direction and magnitude of flow; numbers are megatons (millions of tons). Credit: Steven Davis/Carnegie Institution for Science

Goods bought in the richest parts of the world effectively export CO2 emissions to poorer countries, a factor overlooked by governments’ climate change strategies. That’s the message coming from research in the news this month performed by two separate groups of researchers, one in the US and one in Norway. The Norway-based team of Edgar Hertwich and colleague Glen Peters in particular note that the carbon footprint continues to grow steadily in parallel with how much consumers spend. “There is no flattening out, no indication that the carbon footprint stabilizes at some point,” they write. Consequently, as nations continue to strive to raise their wealth, we might expect their carbon footprint to grow along with it. “This is, I’m afraid, bad news,” Peters and Hertwich say. “We cannot expect that emissions are reduced as a part of normal development.”

Hertwich and Peters last week won an award for the “Best Policy Paper” for 2009 from the journal Environmental Science and Technology that published their work. They looked at all countries’ carbon footprint in 2001, going further than just looking at CO2 produced within their borders to also assess the impact of international trade for the first time. Their results have been made into a website, called “Carbon Footprint of Nations”, which shows how emissions vary with consumption. Greenhouse gas emissions rise about 70% with each doubling of consumer spending, with more emissions coming from transport and consumer goods and less from food.

 The "Carbon Footprint of Nations" website created by Edgar Hertwich and Glen Peters shows international emissions in 2001.

The “Carbon Footprint of Nations” website created by Edgar Hertwich and Glen Peters shows international emissions in 2001.

On March 8 Ken Caldeira and Steven Davis at the Carnegie Institution in Stanford, California, also published a similar analysis of carbon footprints in 2004 in the Proceedings of the National Academy of Sciences. The study finds that, in 2004, 23% of global CO2 emissions, or 6.2 billion tons, were used to produce goods traded internationally. Per person, about 2.5 tons of CO2 are consumed in the U.S. but produced somewhere else. For Europeans, the figure can exceed four tons per person. Most of these emissions are outsourced to developing countries, especially China, where 22.5% of  the CO2 produced was for goods to be exported. “There is little evidence that carbon-intensive industries are being sited in developing countries in direct response to climate policy,” Caldeira and Davis write. “However, industrial expansion occurring in those countries may unintentionally undermine ongoing efforts to regulate emissions.”

“Where CO2 emissions occur doesn’t matter to the climate system,” Davis says. “Effective policy must have global scope. To the extent that constraints on developing countries’ emissions are the major impediment to effective international climate policy, allocating responsibility for some portion of these emissions to final consumers elsewhere may represent an opportunity for compromise.”

Hertwich and Peters suggest that improving production efficiency and using more renewable energy when manufacturing goods would also be useful. Nevertheless, they still seem uncertain that this will achieve enough. “If we really want to reduce climate change, it seems like the consumption of goods needs to be limited,” they write. This would not mean a complete halt, however, as the scientists note that consumption by rich households in both developing and industrialised nations is needed.

Checking CO2 emissions: Watch your energy level

The UK Carbon Calculator website

Pretty is often associated with shallow, but that is definitely not the case with the UK Carbon Calculator website

Before cutting your CO2 emissions you need to know what they are – but not everyone who tries to is successfully making it easy to find out. While Simple Climate has focussed so far on trying to understand what’s going on with climate change, tonight’s is a first step to doing something about it. And boy, am I feeling tired and snappy now.

There are a number of CO2 emissions calculators out there on the internet – and as my girlfriend Kendra and I live the UK, we thought we’d try the British government’s one first. Some impressive design makes it look smart, which is a good start. However, on my computers that made it slow enough that the long waits annoyed even me, who wanted to know the results to write about. If you’re only casually interested, or have a slower computer, it would probably be enough to end your research.

The designers were kind enough to warn us that you might need your electricity and gas bills, plus car mileage and fuel efficiency. What they didn’t say was that we’d also need to know the energy rating and age of all of our kitchen appliances. And details of every public transport journey we’d taken during the year. They also said that we’d be able to go back and update the information we’d already given but we couldn’t figure out how to do this. After four attempts at filling in the survey from the start, we eventually got it right. It told us that our household emissions are 3 tonnes of CO2 per year for transport, power and heating. The site then suggested lots of good ideas for how to cut this. Yet, as Ken pointed out, if you’ve got enough determination to get all the way to the end, you probably know all this already.

A much easier UK-based survey is provided by the Carbon Neutral company. Ken did it in about five minutes using the same starting data that the official government site said it needed, and again got 3 tonnes of CO2 per year. The downside of this is that once you’re done, it just suggests buying carbon offsets rather than cutting your emissions. But like the survey, at least that keeps it simple.

I thought I’d try a couple of US-based sites as well, to see how they compared. The Environmental Protection Agency calculator is a lot more user-friendly than its UK equivalent. A simple web page, with just a few forms to fill in and boxes to check, plus suggestions afterwards how to cut emissions. It said our CO2 output was 2.25 tonnes each year, but given that we don’t actually live in the US this is bound to be somewhat inaccurate.

Another US site, the Nature Conservancy, offered an especially straightforward calculator, which interestingly was the only one to include the impact of the food we eat in our carbon emissions. This site asks simple questions about your behaviour rather than relying on inputting figures. It said our CO2 output came out at 16 tonnes each year, but it also said that the average two person household in the US emits 53 tonnes, compared to the EPA’s estimate of 19 tonnes.

So now you now know not to use the official UK site unless you want to be REALLY thorough, and have plenty of stamina. If you’re feeling especially daring, you could try the sites out for yourself, and share your experiences using the comment tools at the end of this article…