Category: science

Quaternary Park

18/8/2005 /

An interesting idea is doing the rounds in the press at the moment. Around 13,000 years ago (in the Late Pleistocene period) there were a number of extinctions of large mammals in North America. A team from Cornell University proposes to reintroduce large mammals into southwestern ranches. They may start with Asian asses (don’t search Google with that unless you’re open minded ;-)) and Przewalski’s horse, the latter being the only extant species of wild horse and an endangered species. Horses were prevalent in the USA before the last ice age.

Later on in the experiment, they propose Cheetahs and Elephants as other species to introduce into large private parks. North America could once again be home to a number of animals which originally lived in the wild there. One fear I have is that this kind of artificial introduction of species into an ecosystem could have unknown side effects on the food chain; most articles I have read present the positive side in several paragraphs and then just add “the risks are not trivial” at the end. To give a truly balanced argument one might think about the example of Australia where many pests were introduced either voluntarily or accidentally. The whole continent is now home to many feral animals (domesticated animals that have become established in the wild) and rodents which cause many problems.

Turning Mars Green

15/8/2005 /
Suzie

They’re thinking about terraforming Mars. Apparently, molecules which cause a rise in the greenhouse effect could be used on Mars to allow the Martian atmosphere to keep more heat, and hence start to become a haven for life. Octafluoropropane is the gas which could do the trick. Suzie (pictured) thinks that’s all a load of rubbish, since it’s not likely to happen in her lifetime. She’s usually right, but since the research was done by Margarita Marinova, who could be a distant relative of a tennis player, then it could be true.

I’m really tired after battling with the bathroom decoration yesterday and today. It took me a whole day to strip the old wallpaper from the walls, and then there was more stripping, sanding and undercoating to do today. I will have to wait until tomorrow to put the first coat of paint on. It’s single coat, and hopefully one coat will do. Usually when you pull wallpaper off, you have nasty surprises about the state of the walls behind. There was a hidden bonus for me though : I discovered a recessed hole for an electric socket (ready wired and just waiting for the socket itself) that had been papered over. I tested the wires and there’s voltage there. So Yasmina may finally get her electric towel heater since my final argument that there wasn’t a convenient power source is now defeated :-(.

Global Warning?

11/8/2005 /

A recent article on Yahoo! collates a number of pieces of anecdotal evidence of species of fish, birds and locusts being found further north than usual. Scientifically speaking this kind of evidence cannot be directly linked to global warming, but it’s a possible warning sign. Just like if you see animals cowering outdoors or seeking shelter, it doesn’t necessarily mean there will be a thunderstorm, but quite often a storm will follow. You cannot state – scientifically – that animal behaviour either causes or predicts thunderstorms.

Some rather more scientific evidence based around the global temperature record seems to point more convincingly towards a small rise in temperatures, between 0.4 and 0.6° celsius. This evidence shows a warming trend, but fluctuations in temperatures of the Earth have happened in cycles for millenia and some people openly state that this fact is often ignored.

Fred Singer, a Ph.D. in physics from Princeton says the following :

[…] observations show that sea level has risen in the last 18,000 years by about 400 feet and is continuing to rise at a uniform rate, and is not accelerating, irrespective of warming or cooling.

The strongest scientific facts I could find are here, from which I quote :

Climate change is controlled primarily by cyclical eccentricities in Earth’s rotation and orbit, as well as variations in the sun’s energy output.

On one hand, the press seems to pick up on many anecdotes as pointers to global warming. Fear and doubt sells newspapers. On the other, scientists and long term records show that we are part of inevitable warming and cooling cycles which are beyond the control of humans. However, this does not mean that we should allow gratuitous pollution to continue, because other more serious effects of releasing noxious gases into the atmosphere are a public health concern of a different kind – notably a prevalence of asthma and other breathing problems in industrial regions.

Do not confuse climate models which predict warming with rather more widely accepted research about ozone depletion which causes more harmful ultraviolet radiation to strike the Earth, and caused a widespread reduction in the use of CFCs.

Perhaps you disagree with me, but I’m afraid for the moment I’d have to say I would rather play cautiously and reduce CO2 emissions for a number of other reasons than an imprecise fear of global warming. Carbon based fuels will not last forever at current consumption levels. A lot of fuel is wastefully burned in inefficient ways – especially in large engined motor cars. This waste worries me far more than a fear of possible global warming. Science should allow us to be increasingly abstemious with resources, and yet with industrial and scientific progress waste seems to increase!

Perhaps controversially, I might give the last word to Fred Singer, who says :

[…] there are many more important problems in the world to worry about, such as diseases, pandemics, nuclear war and terrorism. The least important of these is global warming produced by humans, because it will be insignificant compared to natural fluctuations of climate.

Flying on Mars

26/7/2005 /

There exists a flight simulator written by a rather eccentric but clearly intelligent guy, Austin Meyer. It’s called X-Plane, and it’s based on blade element theory which breaks down the plane into lots of small sections and calculates the forces on each section many times a second.

What’s most unusual about it is that it’s pretty much a one man show, and the author is clearly passionate about what is going on in the software. The page most worth a read is probably the page about flying on Mars, since Austin Meyer loaded freely available NASA data about the atmosphere on Mars, the topography, and gravity.

It’s sort of wacky, but you’d be hard pushed to find a computer geek / plane nut site more complete that recounts flying on Mars…