Tuesday 29 May 2012

Standing up for Science

“We try to get it right, and we are generally nice people!” If people feel the need to confirm this something is probably wrong. So who was saying this to whom? It was a science journalist in front of a room full of scientists. They should be the best of friends; science journalists wouldn’t have a job without scientists, and scientists would struggle to get their work noticed by society without the science journalists. But a lot of mistrust hangs over this collaboration.

Where did this attempt to bridge the abyss take place? At a course on science communication “Standing up for Science”, organised by “Sense About Science”. The latter is a charity aimed at helping scientists to get their message across, and helping the community to find the scientific support it needs. They were approached, for example, by an organisation of fire fighters, who were worried about clambering around on roofs just next to phone antennas. Would the radiation pose a threat? If one asks internet one can get all sorts of loudly proclaimed opinions, but who to trust? Sense About Science will show you the way!

The glamorous venue at Belgrave Square, kindly provided by the Society of Chemical Industry


Another of their actions has been to write a flyer on the peer review process. For those unfamiliar with it; it is the selection process scientific manuscripts go through. If you send one to a journal, the editor will ask a few fellow experts in the field to review your manuscript. They can recommend publication as is, revision, or rejection. The editor has the final say. As scientists have something to lose by letting standards slip, this process tends to be very thorough. Sense About Science has explained it a bit better than I just have. They point out the merits, but also the weaknesses of this process. And explain the relative merit of peer-reviewed sources compared to other sources. And they have sent 1/2 million copies out in all directions, making it a part of civil service training and a school resource. One could assume many lay people would not be aware of this phenomenon, and might make the mistake of equating proper scientific literature with, say, any polemic in a blog. They also sent a flyer about statistics and how to make sense of them to it to all MP's and lords in the houses of parliament! And I don't know how many of these flyers have gone linea recta into the waste paper bins, but every single one that is read and taken heed of is a major triumph.

At this occasion they had organised a workshop for early career scientists to give them some advice of getting their message across. In order to do that they had invited three panels of experts: one with researchers who had lots of experience with the media, one with science journalists, and one with people such as media officers.

One of the researchers, Steve Keevil of (among others) King’s College in London, had a fascinating story to tell. He was involved in MRI science; something evidently very societally relevant. His field was shaken up when an EU directive would become effective which would seriously limit the use of MRI. All with the best intentions, but in effect severely limiting the diagnostic methods available to the medical profession. He had alerted some powers that be, but these had just said he had to live with it. EU directives are irreversible!


The panel of researchers. With Steve Keevil talking


He had then contacted Sense About Science. They had advised him to send out a press release and hold a press conference. He thought they had gone mad! But he did it. And it caught the attention of the public. And through that, it caught the attention of politicians. Before he knew it he was on a panel that advised parliament. That EU directive has been postponed more than once. And is likely not to be passed at all. Victory!

The journalists, after reassuring us they’re not trying to stitch us up, also had interesting stories. One lady working for science programmes on the radio (Michelle Martin) said she often phones scientists to see if they are willing and able to collaborate on a programme. And that phone conversation is the dress rehearsal. So scientists; don’t save your brilliance for the actual interview; if you do that it may not come!

The last panel included a lady from SAS itself. She encouraged us to become a member of their network “Voice of Young Science” (VoYS); the people they call on if they get a request from the public. They always have use for more people! And it is a great chance to now and then really make a difference. I was glad to hear that you don’t actually have to be below any specific age to join...


A selection of publications SAS has produced


With all these panels the room had lots of discussions, and between these sessions there were group discussions of only the scientists. It was great to hear all these things, get all sorts of new ideas (I’ll start tweeting! And join VoYS! ) and make contacts with all these other people out there who are interested in science communication.

My last question was if someone had a tip on how to deal with aggressive comments. One quite regularly bumps into climate sceptics who think all scientists are part of some nasty conspiracy, and they are not particularly keen on listening to a balanced scientific argument. It’s all part of the conspiracy, right? A Danish girl stepped in there, and said she had witnessed an astronomer being interrupted by someone saying “but the moon landing, that was all fake, wasn’t it?” The astronomer then didn’t open a register of scientific publications based on the moon landing; he just said “if it was fake, don’t you think the Soviets would have found out, and loudly exposed this scam?” I should keep that answer in mind...

Monday 21 May 2012

How to make a sea level record

“So how do you know how high sea level has been in the past?” I get that question a lot. It’s a good question; if you’re not a sea-level scientist (because that’s cheating) you might wonder how something as elusive and evanescent as sea level could be traced back in time. One may think of marine features above the reach of modern tides such as raised beaches, or coral reefs, or signs of wave erosion, such as wave notches. And as signs of sea levels having been lower one can think of drowned ruins. But these are all isolated indicators. What if you want to know what happened over a long period of time?
A fossil coral reef in a forest, which is clearly a terrestrial environment; a clear indicator of relative sea level having been higher in the past. Picture taken in Windley Key Fossil Reef Geological State Park

 
When geologists and geographers want to have a continuous record of something they often stick a corer into the ground.  If you pick the place where you do that right, you get a core comprised of sediment that has been deposited over the time period you are interested in, and contains the information you need. So just suppose you want a sea level record that goes back 500 years, how would you go about that? You need to find a place near current sea level where sediment has been deposited in a calm environment for quite a while, and where there are things in the sediment that record the position of the sea. Think about it: not many places will do. Many coasts are erosive. Many are energetic. Many just contain sand, with dead shells, that have washed ashore. So what did the scientific community come up with? The salt marsh.

 A salt marsh
A salt marsh is an environment that gets flooded periodically by tides, and where salt-tolerant plants grow, trapping sediment. If sea level rises slowly, they can build up; if it drops slowly, they can build out, provided there is space for that. If sea level changes too fast the marsh will become either a fresh-water environment, or drown.
On the surface of salt marshes not only plants grow; they tend to host a plethora of micro-organisms too. Among these are foraminifera and diatoms. Foraminifera are small animals that build a shell, either of calcite or of particles they find. Diatoms are algae that build a kind of shell from silica. And there are countless many species in either group. And all of these species have their own preference for how often they are in the water and how often they are dry, and how salt the water is they live in, and many more of these factors. In other words: they are picky about where they live with respect to sea level. And the good thing is: they take that pickiness with them into their graves. The organisms themselves decay, but under favourable circumstances their shells are preserved. Ready for a passing geographer to interrogate…
A sediment core from a salt marsh

What we do is roughly as follows: we take samples from the surface of the marsh over a transect from high to low. We also take a core, trying to get the location right so that the entire period of interest is preserved in its sediments. Using surveying equipment we find out at what elevation these are all taken from.
Later, in the lab, we determine which species of the microorganisms of our choice we find in the surface samples, and their absolute and relative abundance. That tells us at what elevation the various species live. Then we determine the species assemblages in samples taken from the sediment core. Given that we have established at what elevation interval these species live we then know at what elevation these samples must have been deposited. And if we, for instance, take a core and find an assemblage typical for an elevation of 30 cm above sea level at half a meter down in the core, we know that when these sediments were deposited sea level was 80 cm below the current land surface. And if you do that for every centimetre of the core, you get a rather detailed record. If you then manage date the core with good precision you have your sea level reconstruction!

This is what you would then see through your microscope. A salt marsh foraminifer is encircled.

We tend to look for salt marshes with a tide gauge nearby; these record sea level in real time. The oldest records go back hundreds of years; if our reconstructions match these records we have faith in them, and assume they also describe the period from before the start of the tide gauge record as reliable.
So after all that work, what are the questions we want to answer with this kind of research? There are many. One is, for instance, if we find accelerations in sea level rise of which the timing is consistent with the industrial revolution as a possible cause. Another one is how fast such accelerations in the past have been; it might be good to know how fast such processes can take place. Another one is if we can attribute specific sea level changes to specific ice caps; if so, we get some idea of what to look out for. If the West Antarctic Ice Sheet has collapsed in the past, and we can figure out how fast that went, we know what to get ready for. It may happen again! And how we can distinguish between the various ice caps (there are many other sources of sea level change, of course, but in the long run the ice caps are the biggest players) is material for another entry…

The author on a body of ice. Not an ice cap, admittedly.

Tuesday 8 May 2012

iGlass

iGlass
“Don’t get bogged down in the marsh work!” Whether that was a witty comment or not I’ll leave to the readers, but it sure was the concluding remark of the iGlass kick-off meeting. Some may think iGlass is one of the newer Apple products; it seems there once was an April Fool’s day spoof claiming Apple had indeed produced some sort of cyber-glasses. And there's more of such to be found; no idea if they're real, but there seems to be an iGlasses app that distorts images, and there are iGlasses for the blind, with obstacle detection... But in this context it’s a big scientific project, funded by the Natural Environment Research Council (NERC), aiming at studying interglacial sea level.
So why is interglacial sea level worth so much of your tax money? We are currently living in an interglacial, sea levels are rising, and billions of people live pretty close to sea level. In order to not let the lives of countless many of these get disrupted we need to know how fast sea level can rise under circumstances like those of today. And where can one find information on such things? In past interglacials. Earth has experienced a switching between cold (glacial) and warm (interglacial) states for roughly a million years now; an interglacial occurs approximately once every 100.000 years. Sediments from these periods have survived, and they contain a wealth of information on the environment in these periods, available for those who are willing to interrogate them thoroughly. And that information will provide a good idea of how fast sea level can rise by how much in times like ours.
Policy makers need such input to base their adaptation policies on. If you know within what range sea level changes will be, you might know whether you can get by with strengthening your defences, or whether it’s time to start building wholly new ones. Or perhaps plan a retreat, if defence isn’t economically feasible.

So why the reference to marsh work? This project seeks its data in four fields: sea level information contained in dripstone cave sediments (speleothems), corals, Red Sea sediments, and tidal marsh microfossils. And yours truly is part of the team that will scour the lands for interglacial salt marsh sediments to which we can apply our usual method of sea-level reconstruction. What is that? Explaining that will take another blog entry. We have already found salt marsh sediments with micrfossils we can prod. That, too, is material for another blog post. The project will run for four years, three of which involve me; the stream of blog entries from this project will be considerable. Welcome to iGlass!