Having head in the clouds part of job


Unlike the stereotypical scientist pouring chemicals into test tubes and leaning over a Bunsen burner, a large part of atmospheric scientist Alex Geddes’ work is made up of computer programming and improving codes.

Originally from the United Kingdom, Dr Geddes completed a PhD in aerosol physics before working in Canada. He moved to Lauder about a year ago, where his work ranges from improving computer programs to capturing clouds on camera.

One of his projects involves collaborating with the University of Leicester to track aerosols in the atmosphere, a follow-on from his PhD research.

“I specialised in the remote sensing of aerosols and satellites, so I used satellites to measure a spectrum and from that working out how much aerosol and where it is in the atmosphere.

“To understand climate change and the kind of radiated balance – what’s the difference between the energy coming in and the energy going out – you really need to understand what aerosols are doing.”

Along with clouds, aerosols were probably the biggest uncertainties in understanding climate change, he said.

“They’re really, really important but they’re incredibly hard to measure.

“It’s one of the more important things I’ve been working on.”

In addition, he is working towards a paper on how scientists can study images from camera systems, in particular clouds. Unlike the human eye, the computer cannot register contours and gradients in the sky.

“To do that programmatically is actually quite tricky. You’ve go to come up with ways of dealing with that kind of thing – making sure that your measure of how much cloud is in the sky, which is typically what we’re trying to get from these instruments, is good and semi-realistic.

He had been developing “new, smart ways” of doing that using modern imaging processing techniques.

“It’s super nerdy stuff .. I think it’s quite interesting.”

His work involves collaborating with the University of Hanover, comparing data from cameras based in both Germany and Lauder.

“I’ve got all the data I need to [make a] sort of hemispheric comparison.

“One of the big differences between the northern and southern hemisphere is the amount of clouds and what those clouds look like.

It was interesting to assess what the differences were between New Zealand and Germany, which had a similar latitude, Dr Geddes said.

However, the comparison could be difficult “because obviously Germany’s inland, but it’d be interesting data to have a look at”.

His programming work ensured measurements taken by the instruments were efficient and reliable, which was where Lauder’s value lies.

“That is the core of what we do here. We’re a long-term measurement site, so our value is in providing this data that is good, robust and is not going to have any errors in it or anything too wrong with it.”

He had known about Lauder for five or six years, because it was well regarded for having excellently maintained datasets and good-quality measurements.

“It’s incredibly important. It means we don’t have as much time to do what we’d like to do which is actually research . . . it’s a constant battle of trying to keep things alive, keep things going and modernise, upgrade.

“We don’t really have an agenda in what we’re trying to find, we’re just getting as good a data as we can and then from that assessing what we can draw from that data,” he said.

The goal was to “take a really good measurement”.