Friday, July 23, 2010

Climate change and the election: who to vote for?

This is a post that I was not going to write. But I think at this point I have no choice. I am recommending a vote for the Greens in both the House and the Senate. And in terms of preferences, my strong feeling is that neither major party should be preferenced. While not preferencing them in the House is impossible, it is possible to leave the two major parties unpreferenced in the Senate if there are 20 candidates. This is because the rule is that you have to preference 90 per cent of the candidates. So, if there are 20, you can leave two spaces blank.

This is, however, only really possible in the ACT and the Northern Territory, as there will only be two candidates from each major party. Given that there will be 6 candidates from each major party in the states, it might be a little difficult to dump all of them - there would have to be 100 candidates. But you can at least preference them in the reverse order to that which they tell you to on their how-to-vote cards.

Note that your preferences are not determined by other parties unless you let them. If you vote above the line in the Senate, then sure, the party that gets your vote will decide where your preference ends up. If you are not lazy, however, and can spare the time to write a few numbers in boxes, you get to decide where your preference goes. It astonishes me how many people do not understand this point - the fault of the media, I guess, and of parties who want others to believe that they decide preferences.

So: vote Green. And do not preference the major parties, except in reverse order.

Monday, July 12, 2010

How to show that Arctic warming is affected by atmospheric CO2?

It is often asked by those who are sceptical of the warming influence of CO2 for evidence that the recent rapid melting of the Arctic is being caused by human created greenhouse gases. The above graph is something that everyone interested in this issue should pay attention to. What is shows is that there is a statistically significant correlation between the natural logarithm of atmospheric concentrations of CO2 and the temperature of the Arctic as measured by UAH. And the temperature of the Arctic certainly has an impact on Arctic ice. The data is taken from these two sites:

While this graph is not proof of a link, it is indeed evidence - all that science can provide. It should be noted that what the slope of the graph shows is that the climate sensitivity of the Artic region is seven degrees. In other words, for every doubling of CO2, the temperature of the Arctic as measured by satellite is projected to increase by seven degrees celsius. The speed of Arctic warming is thus between two and three times that of the earth as a whole - the range that was projected by the IPCC ...)

(The calculation of this is done as follows: take the slope, which is approximately 10, and multiply it by .7 - the natural logarithm of two, a doubling. This gives you the projected increase in temperature per doubling.)

Monday, July 5, 2010

Inflow into dams and rainfall for the first half of the year

So we now have data for roughly six months - rainfall data for six months, but dam inflow data for slightly less than that (I am extrapolating out to six months from the data that I have).

We have had 336.4 mm of rainfall so far this year, above the average by around 30 mm.

I have measured 29,500 megalitres of inflow. Extrapolating over the period that I have no data for, that suggests that we have had 32,000 megalitres of inflow this year so far.

While we have had an excellent year of rain, we are still headed for a very low year of dam inflow. If we get 700 mm of rainfall this year, we will get around 66,000 megalitres of inflow. But I do not think that that will happen. My prediction is still for less rainfall than 700 mm and inflow of around 60,000 megalitres.

The fact that this has been a high rainfall year but that inflow is low should be sending warning signals to all in the ACT about the risks that climate change poses to our water supply. While ACTEWAGL are taking steps to ensure our water security, they are not moving fast enough. Without public pressure, it is doubtful that the government will act.