Svalbard: no bubbles or bears detected

Svalbard airport. No bears (armoured or otherwise) in sight.

The only things that anyone* ever wants to know about Svalbard are: did you see armoured bears, and did you see any methane bubbling up form the clathrates? Well, I’m sad to report that on first look, we detected neither.

*OK, so maybe not anyone. Maybe just me. Most people probably have no idea what I’m on about. So for the 99%, I’ll explain. Armoured bears are in Philip Pullman’s His Dark Materials trilogy (highly recommended reading, IMHO). I won’t expand on that point. What I will expand upon is the bubbles, as we flew to Svalbard yesterday to see if we could find any evidence of them.

The bubbles of methane are released from structures on the bottom of the ocean, which are called methane clathrates, gas hydrates, or some variation thereof. I think these are very curious entities, probably because I don’t know enough about them. For now, I’ll just say that the gas hydrates are crystalline structures of water and methane ice, and methane is trapped within the structures. Sometimes, the methane can escape the structure, and bubble out into the ocean. There is a line of these gas hydrates just off the west coast of Svalbard, and methane has been observed bubbling up from the structures underwater. The methane dissolves in the water while it rises to the surface, but the question is whether all of it dissolves, or if some gas can escape to the air.

It was this source of methane that we went looking for off the coast of Svalbard. We didn’t observe higher concentrations of methane in the air while we were there, however it’s still possible we could detect some signature when we get the final analysis done in the lab (and by we, I mean colleagues at Royal Holloway, Manchester, FAAM, etc, and not me!).

Even if we don’t see any emissions from the gas hydrates, it doesn’t mean that it never reaches the atmosphere. The gas hydrates only trap the methane effectively at certain temperatures and pressures. If the water warms, the gas hydrates could potentially release considerable amounts of methane. If the sea is warming gradually, we may reach a point where lots of methane starts to be released. So it’s possible that under most conditions, no methane escapes. But then once the temperature crosses some threshold, it could then start to be released. What we want to know is whether any of this can get into the atmosphere, where it would cause more localised warming.

So that’s why we went off to Svalbard in summer. We also looked for, and found, regions of the atmosphere with more methane than the general background. This is one thing that I’m really interested in. I want to use a model to work out where these high concentrations of methane come from, and see if that’s consistent with the sources suggested by the isotopic analysis. Judging by the meteorology, I think the sources will be Russian (gas) or Scandinavian (wetlands). Watch this space (for a very long time) to find out if I’m right!

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Arctic methane, here we come!

A quick snap of Stockholm, Sweden, today. Lucky it’s not possible to get to Kiruna from London in a single day, eh?

Today, I’m setting off for Sweden, to take part in field work for a project about Arctic methane (MAMM – methane in the Arctic, measurements and modelling). The research aircraft is going to be based in Kiruna, Sweden, and will be arriving there tomorrow. We’ve got a stop over in Stockholm to get there on a commercial flight, as we can’t do the journey in one day. It really is quite far north – the northernmost town in Sweden, where I don’t think it even gets dark at this time of year!

The aim of the project is to find out more about the methane (CH4) emissions in the Arctic, which are not very well known. Not only are the measurements in the Arctic quite sparse, as it’s rather remote, but the emissions are also very variable. One large source is wetlands, where bacteria produce methane (I’m no biologist, but wikipedia has an entry on wetland methane emissions). As the temperature increases, more methane is emitted. There are widespread wetlands in Scandinavia, and we have colleagues taking measurements there at the moment. Hopefully we will be able to fly over them and take more measurements, so we will be able to observe methane on the local scale, and the larger scale by the aircraft. Another source of methane is from “thermokarst lakes”. These are lakes that are frozen in winter and melt in the spring/summer, which releases methane.

One possible outcome of any Arctic warming is that there could be a positive feedback. This is because methane is a strong greenhouse gas (it is many times more potent than CO2 as a greenhouse gas, which I could go into in another post). Local emissions of methane will cause a local warming. As increased temperatures lead to more melting, and more release of methane, you can see how this could continue on and on! There is also a hypothesis that increases temperatures in the Arctic could be contributing to the bizarrely south-of-the-UK jet stream that we currently have, which has brought us immense amounts of rain. More on that on the Met Office blog.

So, what will I be doing for my field work, seeing as I usually live in the model world? Well, so far this week, I’ve been part of the group who are flight planning. We’ve been keeping a close eye on the forecasts for the European Arctic region, to try and plan the most suitable places to fly each day. We’re only flying Friday through to Monday, so we don’t have much room for manoeuvre, as it were. We want to link up some of the wetlands aircraft measurements with satellite measurements, but the satellite can only measure when there’s no cloud. Unfortunately, it’s looking like it might be cloudy at various times over the weekend.

We also want to go north to Svalbard. Hopefully we won’t see polar bears. What we do want to see is some methane coming out form the ocean. There is an undersea ridge, where methane trapped inside clathrates is released. There is definitely methane coming out form the vents (see a paper by Fisher et al, which I’ll have to find the link for later), but the question is whether it all dissolves in the water, or is some escapes to the atmosphere.  We shall hopefully find out more over the weekend!

So, that’s just a quick brain dump of what’s going on in my head just at the moment, while I’m on the train to London. Hopefully I’ll have time for more brain dumps over the weekend!

When it rains, it pours!

Rainfall at my weather station for first half of 2012

Rainfall at my weather station for the first half of 2012, alongside 1971-2000 averages for the Met Office’s station at Bedford. See how we caught up once the hosepipe ban kicked in! (Click to see full size.)

Can you guess when the hosepipe ban started? It was on the 5th of April. By the end of April we were catching up with the cumulative average. I guess we should all be joyous that the rains have finally come, and we aren’t running low any longer. It’s about time too!

So, to backtrack a bit. Dr Turnip got me a fancy-pants weather station for Christmas (the one he wanted to buy was out of stock, so he went for the next one up!), and so I am now able to plot up my extremely local weather data, which has been collected on the very non-standard roof of our canal boat. Despite being a pretty cool bit of kit, it’s not a very good location for collecting weather data as the boat rocks about a bit, and the boat will radiate heat and reflect light from the roof, and the marina is surrounded by trees, which deflect the wind.

So, every quarter (ish) I download the data and take a quick look. As we were in drought earlier in the year, and then we had such a lot of rain more recently, I thought I’d plot it up and share. The graph shows cumulative rainfall from my rough-and-ready weather station since January. I was a bit negligent and didn’t download the data in time, so there’s a gap in April where the data was over-written. I’ve also plotted up the Met Office 1971-2000 monthly averages for their Bedford station (which can be found at http://www.metoffice.gov.uk/climate/uk/averages/19712000/sites/bedford.html). This shows that in the first three months of 2012, here in the south east of England we were much drier than usual. Then the hosepipe ban came into force of 5th April, and everyone started sacrificing their lawns, flower beds and car hygiene in the name of the rain god.

Then in April, we started to see more rain than average, which was totally unrelated to the sacrificial lawns, I’m pretty sure. (NB the totals in my plot are a bit off for March and April because of my lost week which fell over the 1st April. Hah! What a fool I am.) My total for 23 March – 30 April was 90mm. This would equate to about 71mm for a 30 day period, and the average for April in Bedford is 47mm — so we got 50% extra free this April! Bargain!

The River Great Ouse overspilling

I took this photo in Bedford on 2 May 2012. This tree is not usually in the middle of the river… that was down to the bonus rainfall we had in April.

And then May was only slightly above average. But then June. Well. We got 66% extra free. That’s 66% more than usual. And it really felt it. And lo – we caught up with and surpassed the average year-to-date rainfall. Sounds good, right? Not entirely. As you can see from my photo above, the River Great Ouse in Bedford burst its banks. Luckily, we didn’t have it too bad here. Others in parts of the UK had their homes and possessions ruined by flooding, and some poor souls even lost their lives. This kind of unusual weather means that we often aren’t prepared to deal with it. And if this kind of thing is going to become more common, we’ll have to adapt. (One reason why I live in a boat!) But the $64,000 question (in fact, it’s worth a whole lot more than that) is: is our climate is changing to one that has more of these extreme weather events? Only time will tell for sure. But one thing I can say for sure now: by then, the damage will already be done.

Postscript:
That ends on a a bit of a downer. So to pick things up again, check out this article and cool video: http://www.channel4.com/news/met-office-rain-plane-on-course-to-chase-storms. It’s about some work that people are doing using the UK’s atmospheric research aircraft, which I have done/will do field work on. Lots of people are working on finding out more about severe weather and predicting it (not me though). So things aren’t all doom and gloom!

Stock market crash hits EGU General Assembly shocker!

Here’s the second of my GeoLog guest blogs about the EGU General Assembly 2012, which originally appeared here on 2 May 2012.

It seems the global economic downturn is so pervasive that it has even hit the Earth sciences! I’ve been to a few talks now that have mentioned the downturn/recession/crisis/apocalypse (delete as appropriate), mainly with reference to emissions of pollutant species or greenhouse gases. I guess this is one of the few good-news stories to come from the bottom falling out of the world’s economy. With no money to burn, production and therefore emissions decreased, thus slowing emissions – ever so slightly.

On Tuesday, Jintai Lin presented some work on NO2 columns measured from space, which he used to back out the NO2 emissions coming from China. (NO2 is itself toxic, and a precursor for ozone, which is a greenhouse gas and is harmful for animal and plant health.) His analysis of the seasonal variation in NO2 showed that the emissions were dominated by anthropogenic sources. Presenting a time series of NO2 columns from satellites, he showed the unmistakable signal from the Chinese economic downturn in 2008-9 (see figure 3 in Lin and McElroy 2011, ACP), and he showed the same signal in aerosol optical depth (a marker for PM2.5 – see my immediately previous blog post for a definition). But this was not to last, as the NO2 caught up again after about a year and a half.

Shenzhen, PRC

Gratuitous pretty satellite picture alert! Evidence of urbanisation is evident in these two images from 1999 acquired by the Landsat Thematic Mapper, and from 2008 acquired by ASTER. (Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team )

Then on Wednesday, Patricia Castellanos showed a similarly striking graph of a stock index (I didn’t catch which one) on the same axes as measures of European industrial activity and road transport. As you might have guessed, they correlated perfectly, all dropping off the edge of a cliff over the space of a few months in 2008. By dropping off a cliff, I mean a 20% decrease in industrial activity and 15% decrease in commercial road transport. Castellanos summarised this effect with what I found to be a surprising finding: NOx is 10-50% lower now than it was in 2004 (that’s not the surprising bit), and at least half of this reduction was due to the recession.

So, for all the EU’s hard work in making policies and targets for air quality, in regulating vehicle emissions and all the other things they are doing to improve the air we breathe, it has at most been as “good” as the recession for reducing NO2 levels. If they are really serious about air quality, policy makers would be wise to reconsider their attitude to economic growth…

Megacities at EGU 2012

I recently attended the EGU’s General Assembly in Vienna (great conference, guys!), and wrote some posts for their GeoLog blog. Here’s the first, which originally appeared here on 26 April 2012.

Almost a whole day’s worth of sessions on megacities – where to begin? I certainly couldn’t pick just one talk to write about, so here’s a mish-mash of the session in general and a few talks in particular.

First things first: what is a megacity? Officially defined (by who, I don’t know) as a city of 5 million people or more, there are only two of them in Europe (London and Paris), and both are among the most polluted cities in Europe. There are other European places that embody megacity characteristics without adhering to the strict definition, so the MEGAPOLI project has focused on two of these alongside the two bona-fide megacities. The Po Valley in Italy, surrounded by mountains on three sides, is populated by 16 million people and contains 37% of the country’s industry. The mountains disrupt the large-scale meteorology so that local winds are often slack, which combines with the high levels of industrial, agricultural and residential emissions to cause worse air quality than in either Paris or London.

Loss in life expectancy from PM2.5

Loss in life expectancy (months) attributable to exposure to anthropogenic PM2.5 for year 2000 emissions (Source: EC, IIASA)

The air quality is similarly poor in the Rhine-Ruhr valley in Germany, an industrial region with about 10 million inhabitants. This region suffers not only from local emissions, but often from pollution transported from London, Paris and the Netherlands in the prevailing winds. (Thanks to the MEGAPOLI website for the info about these locations).

The reasons why these non-megacities have been brought into the fold highlight the complexities of trying to understand what might happen in the coming years as the world becomes increasingly urbanised. It’s not only the amount of stuff being pumped into the atmosphere that causes air quality issues. It’s equally how much stuff gets vented out of the boundary layer (the lowest layer of the atmosphere, where people live), and how much gets washed out in rain. And what happens to the stuff before it gets removed? And this is not even considering the climate impacts of all this stuff is getting higher up into the atmosphere, where it has a longer lifetime and can be transported long distances, potentially also affecting air quality downwind. All these interactions could be broadly categorised into: emissions, boundary layer meteorology, deposition, chemistry, global transport, and climate.

Several talks in the session were related to emissions evaluations, as how can we hope to understand anything if we’re putting the wrong amount of stuff into the atmosphere? Any by “stuff”, I mean NOx (the sum of NO and NO2, which are pollutants emitted from both anthropogenic and natural sources, and can react to produce ozone, which has adverse health effects) and particulates (the shorthand for particulate matter is PM2.5/PM10 for those with a radius less than 2.5/10 microns, also bad for health), as these were the main topics in the session.

Generating emissions inventories is no trivial task, as is evidenced by the continual work going in to this area. In his talk, S Sahu described the development of an emissions inventory for Delhi and the surrounding areas, which is home to a staggering 30 million people in an area of 70 km x 65 km. For 6 months, an army of 250 students surveyed the residents and businesses to determine a sample of the emission-generating activity in the region. They combined this new data with the existing literature and government statistics to develop a GIS-based emissions inventory. Their results showed that there are 5.7 million vehicles on the roads, and 1.5 million living in slums and cooking with wood, kerosene or LPG (in order of decreasing precedence). The PM2.5 emissions total was 68.1 Gg/year, the largest portion of which was from transport at 30.25 Gg/year. Wind-blown dust and residential emissions were also large contributors. The inventory was used to forecast for the Commonwealth games in 2010 and is currently available for both science and policy uses.

Policy issues were the driver behind R Friedrich’s talk, which directly addressed questions of whether air quality policies could result in the desired policy outcome – surely an important factor in decision-making. As part of the EU MEGAPOLI project, his work took a “full chain approach”, whereby the scenario with and without the policy measure was modeled to determine the effectiveness of a policy. The reference scenario assumes the current EU energy and climate package was taken forward. Then each policy was added to the model, and the difference can be described in monetary terms or by DALYs (disability adjusted life years).

The study generated some surprising results. Twenty four policy measures were ranked in terms of avoided DALYs for Paris, and the best measure by this metric was to change to efficient combustion of gaseous fuels (which generate less PM than wood), followed by biomass fuels. However, different metrics paint a different picture. Calculating the efficiency of each measure in monetary terms put coke dry quenching (as opposed to wet quenching which generates PM) in the top spot, followed by use of biofuels, use of district-wide heating networks, an aviation kerosene tax and a switch to electric vehicles. The least efficient measure was a passenger car toll (which, for example, London has had since 2003). Interestingly, the implementation of a low emissions zone was shown to have a negative or neutral effect. On the other hand, the speaker recommended the improvement of traffic management as an efficient measure.

Another EU project, CityZEN, also linked the science with policy needs by producing some 2 page policy briefs on ozone, PM, observations and the East Mediterranean air pollution hotspot, and was discussed by several speakers. Other talks and poster covered the links between meteorology and chemistry, observations and models, but I’m afraid this is all I have time for… See you next time, on the GeoLog.

What do I do all day?

what i've been doing all day

Science in action! Well, maybe "in progress" would be more accurate...

I ask myself this question frequently, usually when I review my to-do list, and wonder how I’ve managed to take so much longer to complete the tasks than I originally planned. Today, for example, I spent the whole day working on a program that will automatically plot some nice histograms of my data. I hadn’t intended to spend the whole day on doing just this, but once I started, it just seemed to eat up the whole day. Worse, the program still isn’t finished! Maybe it’s a problem peculiar to IDL (it is a rather long winded programming language, but you can make pretty plots with it). But I doubt it. IDL just makes it even easier for a small task to take up your whole life. But just think of the pretty pictures it makes!

In fact, the pretty picture bit wasn’t taking the time. It’s the handling of the data, and making the code flexible so that I can feed it a whole bunch of different data, and ask it to sort it in different ways, and to plot it sensibly, all at the touch of a button. So I’m just spending my time up front, rather than later down the line.

So getting back to the question, “what do I do all day?”. Far from being a flippant remark, to anyone who is not me (or a post-doctoral researcher who works in a very similar area of work to me) it is a valid question. You might be curious about what do scientists do all day. You might even ask what scientists spend your taxes on. I can only speak for myself, but I thought I’d give it a go, seeing as I’ve had enough of IDL for one day. As my brain in almost a mush at this point in the day, I thought I’d go through the most mundane of tasks.

I run computer models. I edit the code of said models, to do little experiments and tests (this takes longer than it sounds). I find bugs in the code. I plot up the data from the models, often in comparison to observed data. Sometimes, I will process the data (eg using statistics to understand the data) before plotting the processed data. Hmm, that’s essentially it, I think. And I think that’s actually broadly similar to many other scientists in other disciplines, it’s just the specific methods that differ.

Why do I do all this sitting in front of a computer, writing code when I’m not actually a computer programmer? That’s a very good question, and one which is sometimes hard to answer when you’ve just spent hours, days or even weeks trying to get your code to work. It’s important to remember that these programs and models are just tools to use to try and understand the world around us, and to help answer scientific questions.

But what are the questions, you ask? Well, I think that’s a question for another blog post.

;-)

As light as a paper wasp nest

So a few months back, Dr Turnip (aka Mr Civiltalker) returned from the shed with a precious gift. It was the wonderfully delicate nest of a paper wasp, pictured below. I was quite astonished by it, as I had no idea what it was and had never seen one before. But luckily, Dr Turnip being a life-scientist, knew exactly what it was when he saw it attached to a folded up wooden chair.

Paper wasps make their honeycomb-shaped nests out of wood (or other fibres) mixed with their saliva — hence the name paper. They are very light and quite amazing to look at. Soon after we took the photos, our find blew out of the side hatch and landed in the water, it was quite literally (and I do mean “literally”) as light as a feather. When I reached down to the water to retrieve it before it floated away, the wet part had gone sticky and gluey — rehydrated wasp saliva!

The cells of this nest are open, and contained no eggs (this was back in May), so we may have robbed a potential wasp family of their home. As there were only a few cells, I am guessing that it was unfinished. Individual eggs are laid in each cell of the nest, and the larvae are fed other insects by the queen. When they are ready to pupate (turn into a pupa), they seal over their cell, from which they will emerge some weeks later as adult wasps.

We used to have a wooden garden table and chairs, which we left outdoors when we lived in London. That got stripped of its outer fibres by paper wasps, and it looks like wooden items in the shed might also be at risk of the same fate. If you notice wooden items going a bit splintery, and seem to have sectioned being stripped off, maybe it’s paper wasps harvesting your furniture too?

Thanks to Colorado State University for the background info on paper wasps. Dr Turnip knows a lot more interesting stuff about wasps and their social lives, but I’ll leave that for another time. If you know about paper wasps and wish to add anything, then post a comment below!