Author Archives: alistair

Copenhagen climate change summit – quick explanation

New Scientist has this excellent page with a high level explanation of what the upcoming Copenhagen climate change summit is about and why it is so important to all of us.

Goal
The Kyoto Protocol was the previous agreement on reducing greenhouse gas emissions. Kyoto now needs to be replaced and that is why the world is meeting in Copenhagen.

The world’s nations must agree on how they are going to massively reduce carbon emissions. This is required in order to avoid a dangerous increase in global temperatures.

It is already too late to avoid damage – the goal in Copenhagen is to agree on how to limit the damage we do to ourselves.

Rich vs poor
The rich world has already emitted way more than its share. If we are going to avoid dangerous global warming then the rich world is going to have to foot more of the bill.

Not only does the rich world have to reduce emissions by more, but it should also be offsetting past emissions.

Rich world and poor world carbon emissions share

Deal breakers
Reducing climate change is going to be difficult and very expensive. It requires global cooperation, so plenty could go wrong in Copenhagen.

  • The US must agree on serious cuts (they were the only ones to ignore Kyoto). Getting the US Congress to agree to anything tough is very tricky. If the US is not serious then China and India will start to pull out too. Then the whole deal is pointless.
  • Developing or recently developed nations feel that they shouldn’t be penalized for the past excesses of rich nations. This is reasonable but could be a big sticking point.
  • Oil rich nations may try to ‘torpedo’ the deal to protect their own interests and because they emit huge amounts of carbon.

Why red wine doesn’t go with seafood

One of the first things that I learned when I was a waiter in a seafood restaurant is that red wine doesn’t go with fish.

Why that was, I had no idea. It turns out that nobody else did either.

The Economist has this article detailing how some researchers were able to find the answer.

In an experiment the researchers analyzed wines tasted with seafood and found that wines with high iron content left an unpleasant taste. Generally red wines have a higher iron content and therefore don’t taste good with seafood.

In order to test the hypothesis the researchers changed the iron content in various wines and repeated the test. Sure enough iron content was strongly correlated with a foul taste.

Science is awesome. I must be honest though – I don’t mind red wine with seafood. Apparently the combination tastes very fishy and I like that taste.

Google gives directions in SA

Google have just released Google Maps SA. It’s awesome!

We’ve been able to see satellite images and some road data before. But now there is a lot of road data and you can get automatic directions!

The directions service works amazingly well. I’ve tested it with several routes that I often take and Google invariably got things right – even offering options!

For one test I typed in this exact input:

  • V&A Waterfront, Cape Town
  • Moyo at Spier, Cape Town

The service quickly offered two routes to Spier (N1 or N2).

It estimates time fairly accurately at about 40 minutes (N1 is slightly quicker even though it is slightly further).

Google maps SA example

It also offers step by step driving instructions for the route. Like a poor mans GPS. Simply amazing.

View the map yourself to see what I’m talking about.

Cat spies from the CIA

Acoustic kittyI’ve just read several articles on a failed CIA program to use cats for spying. Se-ri-ous.

According the official documents from the CIA and this article on Wikipedia they ran a program to use live cats as listening devices.

Over several years in the 1960s they:

  • Surgically implanted cats with radio transmitters, batteries and recording equipment
  • Trained the cats to stay close to subjects (this was unsurprisingly tricky)

During the first field test a cat was released to eavesdrop on men at a park bench. Almost immediately after being released the cat was hit by a taxi and killed! Shortly afterwards the whole program was abandoned.

acoustic-kitty-diagram

As hilarious and improbable as this sounds it appears to be true. It has been very widely reported, there are official documents from the CIA, and the CIA certainly did do some weird things.

There is some good debate on the subject in the comments section of this excellent article on Acoustic Kitty.

One of the most plausible alternate explanations is that the CIA set this up as a dummy operation and channeled the funds into something else.

Map of all nuclear test sites – 2000 tests in all

Between 1945 and 2008 more than 2000 nuclear test detonations were conducted.

Amazing. More than 2000 nuclear weapons have been detonated on Earth!

This map (click through for the map) shows the locations of all the test sites. Click on each icon to read more about the site and how many tests were conducted there.

The four test sites related to Africa and South Africa interested me.

  • Seems like South Africa collaborated with Israel in testing a nuclear weapon in 1979 south-east of our coast.
  • The Americans conducted secret test detonations just 1800km from Cape Town in 1958 as part of Operation Argus
  • The French conducted 14 nuclear tests in Algeria during the early 60′s

African nuclear test sites

Analysis of Human Development Index for South Africa

The UN’s Human Development Index is an attempt to quantify quality of life. Three measures are used to create a single human development score:

  • Health (life expectancy)
  • Education (adult literacy)
  • Wealth (GDP per capita)

Using only three variables makes comparison possible, but it does mean that the HDI is pretty crude.

It still makes interesting reading.

The latest report (with data for 2007) has just been released. Norway comes out on top followed closely by Australia.

South Africa comes in at 129th of the 183 countries (some really bad places like Somalia and Zimbabwe don’t have enough data to be on the list at all).

hdi-south-africa-relative

I was particularly interested in the trends over time. South Africa has gained ground since 1980 but has fallen off since a peak in 1990.

hdi-south-africa-overall

Looking at each of the components in HDI it becomes clear that life expectancy is hurting South Africa’s HDI score. AIDS is really holding us back. GDP per capita has also been pretty flat.

hdi-south-africa-components

How has South Africa done relative to similar countries? Let’s compare SA to the 26 countries with the closest HDI scores back in 2000.

Not pretty. As you can see we’ve been in free fall. We went from the middle of this little group to stone last!

hdi-south-africa-same-starting

What about similar countries by geography? Let’s compare SA to our regional neighbors. Clearly our region is struggling, but SA has still lost two places!

hda-south-africa-regional

Computer program generates realistic image from freehand drawings

Believe it or not a computer program called PhotoSketch generated the image on the right.  Based on the freehand drawing and labels on the left!

This is pretty amazing stuff.

photosketch-1

The program processes the input image and searches tagged images for the required components. It can then seamlessly combine the components into an output image.

This is a very early version of the technology and some of the output images aren’t great. But it is still very impressive (project page has more examples).

photosketch-2

Strange ship off Sea Point – Petrobras 10000

petrobras-10000

This ship has been sitting off Sea Point for a couple of days.

It has an unusual structure and looks like a large building at night. I was curious so when I managed to see the name this morning I did some research.

According to Rigzone (there is a site for everything) it is a drillship on the way to explore possible deep sea oil fields off Angola.

A drillship is a bit like a very mobile oil rig. They are used for exploring deep sea oil fields because they can move around far faster than a normal oil rig.

Drillships use dynamic positioning systems to stay exactly stationary while drilling. Using a combination of GPS, wind and motion sensors and a sophisticated computer model the ship can stay absolutely stationary while drilling. Pretty cool stuff.

Why are humans (mostly) hairless?

Most of us are (mostly) hairless. That is very unusual among mammals and pretty much unique among primates.

Why have humans evolved this trait? This New Scientist article outlines some of theories offered over the years.

We still don’t have a conclusive answer.

Theory 1: Avoiding the heat

Perhaps hairlessness made us better running hunters?As humans became savanna hunters body hair was shed to avoid overheating during long runs.

I have blogged before about theories suggesting that the human combination of hairlessness and profuse sweating allows for persistence hunting.

The problem:

Why has no other mammal adopted this strategy?

Many other mammals would benefit from better cooling systems and they all have fur – what is so different about us? Fur actually insulates against heat and the sun as well as keeping us warm in the cold.

Theory 2: Side-effect of big brains

This theory suggests that nakedness is a side effect of growing larger brains. It was noted that:

  • Human brains grow very rapidly just before birth
  • Humans retain characteristics of juvenile apes (flatter faces, bigger heads and eyes and naked skin).

The idea is that the stage just before birth has been protracted to allow the brain to grow even larger.

The problem:

If having hair were an advantage then we would just grow hair later in life. For example, we grow teeth even though we aren’t born with teeth.

Theory 3: No ticks here

Another theory is that we lost our hair in order to avoid ticks and other parasites.

The problem:

Why only us? If this were really an advantage other mammals would have evolved the same thing.

Theory 4: Aquatic ape

Humans are hairless and have a thin layer of fat under their skin. Sounds like whales and dolphins right?

The idea is that our evolutionary ancestors went through a stage evolving in aquatic environments. This could also help to describe why we walk upright.

By otters have thick fur...The problems:

There are many problems with this theory (read about them on Wikipedia). For example, humans can’t hold their breath very well and are not efficient swimmers.

Most importantly, hairlessness is only an advantage in fully aquatic species like dolphins and whales. Even full time swimmers like otters and seals have thick fur and swim superbly. In short, the aquatic ape theory doesn’t work all that well…

The world’s biggest fire extinguisher – a 747

747 fire fighting plane

Wired has this article about a 747 that has been converted for fighting fires. Sounds like a joke, but this is real.

A company spent $50 million converting a 747 into a fire fighting aircraft. It can drop 75,000 litres of flame retardant on fires. That compares very favorably with the 4,500 litres that the normal fire drop planes can carry.

Size isn’t the only innovation. Normal air drops on fires rely on gravity to expel the water for fire retardant. That means you get one drop and then have to go back for more.

This bad boy has a special pressurized system that allows for several drops. That helps when you’re carrying such a huge payload.

The major disadvantage of course is that this monster isn’t as nimble or flexible as the smaller aircraft and helicopters.