20140511_CF
Source: BBC1
URL: N/A
Date: 11/05/2014
Event: Countryfile: "there's growing evidence that climate change is affecting us now"
Credit: BBC1
People:
- Dr. Richard Betts: Head of Climate Impacts area at UK Met Office
- Richard Bradbury: Head of Environmental Research, RSPB
- David Brooks: Agro-Ecologist, Rothamsted Research
- Alistair Griffiths: Director of Science, RHS
- Tom Heap: BBC journalist and presenter
Tom Heap: The British weather can be wild, wonderful and downright weird. In the last few years, we've had droughts, big freezes and the wettest winter on record. So what's going on? While for some these extremes show that our climate is changing - a warmer world, they say, is delivering wilder weather - others, though, say "Our climate's always been unpredictable". The Thames regularly froze over during a period known as the Little Ice Age, which ended in the 19th century. And some believe the Romans took advantage of warmer weather to grow grapes in the north. This time, though, it's the rapid rate of change that's worrying the experts. They say it's already having an impact right across the globe. But where's the proof? For some, it's right here in the British countryside.
[Tom Heap and Alistair Griffiths are walking through an apple orchard.]
[To Alistair Griffiths.] It's like a blizzard of petals, it's great - it's like those Chinese movies... [Voice over.] Spring has come early to the Royal Horticultural Society's gardens at Wisley in Surrey - hundreds of apple trees are in bloom. But although we've had a mild winter this year, the early blossom here is not a one-off.
Alistair Griffiths: We'd done some preliminary work, so we've got data back to the 1950s. And we've also got a weather station here, and we're beginning to look at, sort of, preliminary findings that are showing that flowering is becoming slightly earlier and longer in time-frame.
Tom Heap: You're only going back a few decades, which is a blink of the eye, in terms of climate - how robust can it be?
Alistair Griffiths: Well, it's - we have to continue to collect that data, so that we get a longer dataset, and make that more robust.
Tom Heap: But you, as a gut feeling, are pretty convinced that these trees are experiencing something different than they would have done, you know, 50 years ago.
Alistair Griffiths: I think there's some evidence that suggests that they're experiencing something to do with climate change. Whether it's 50 years ago or not, I'm unsure, but I think the more data we do, we can see that there is some element of changing climate.
Tom Heap [voice over]: While this study may give us clues, it's not yet conclusive. But the RHS believes there is evidence of climate change all around us. It's just surveyed a thousand of its members, and revealed to us more than two thirds of them said they've seen at least some changes in their gardens, related to climate.
Alistair Griffiths: It's told us that gardeners and professional gardeners see that climate change is happening, believe it's happening. There are extreme weather conditions which are more challenging for them, different flowering times - so, early, late, often sometimes double flowering times.
Tom Heap: How strong are these results? It occurs to be that those that see something are the ones that report, therefore it's just a bit biased.
Alistair Griffiths: It is biased, but what it does it it gives us a snapshot of what people are thinking, gardeners are thinking, and allows us to, sort of, do further research to provide them evidence to deal with things like flooding and droughting [sic] and - and that's what we want to do, at the RHS, is provide that advice so that they can garden and enjoy their gardens.
Tom Heap [voice over]: So, the RHS and some members think they're seeing early evidence of changing weather.
[Tom Heap emerges from some trees.] So does the Intergovernmental Panel on Climate Change. It says that global average temperature has increased by just under 1 degree Centigrade in the last 130 years. A small change, but enough to affect our sensitive ecosystems.
[Voice over.] Studies have shown several species of butterfly in Britain are now being found further north, because of warmer temperatures. And they're not the only ones on the move.
Richard Bradbury [to Tom Heap, who is holding binoculars]: We might see a couple of Dartford warblers, just on top of the gorse here, there's a couple of territories.
Tom Heap [voice over]: Scientists also believe some birds are shifting in the same direction. One in particular - the Dartford warbler - is not only moving, it's thriving as Britain slowly warms up.
Richard Bradbury: Dartford warbler is a species which is really quite sensitive to the cold in winter - they need places where the mean temperature in the coldest month is above 2 degrees Centigrade. So traditionally they've been associated with southern Britain. As the climate's changed, this species has really increased in numbers, getting up to about 3,000 pairs - they've colonised southwest England, they've got up into south Wales, places as far north as Cannock Chase and East Anglia, and even a pair in the Peak District.
Tom Heap: So, as we have fewer cold winters, they're doing better and they're able to move further north.
Richard Bradbury: Absolutely.
Tom Heap: The pattern hasn't been consistent, has it - I mean, within the last five years I can remember some very snowy, very cold winters. So how do they cope with, you know, the variation we get anyway?
Richard Bradbury: I think it's the fact that the frequency of these bad winters has been declining, especially through the '90s and the noughties - that's what's been responsible for this really quite dramatic push forward.
Tom Heap: And how convinced are you that this is a symptom of climate change?
Richard Bradbury: Well, it's hard to be absolutely certain, but it's also hard to see that it could be anything else that's responsible for a northward push of a cold-sensitive species like this.
Tom Heap [voice over]: The Dartford warbler may take climate change in its stride, but other birds seem to be finding it hard. The cold-loving dotterel in the Scottish mountains could struggle, because it can't move any higher to escape the warmth. And scientists believe other species may suffer, this time.
Richard Bradbury: Species' ranges do change - they move north and they move south, as the climate changes. What's different this time is the magnitude and the rate of climate change. And the real question mark is whether or not species are able to move at the rate that the climate is changing.
Tom Heap [to David Brooks, as they enter a small enclosure]: So what are we hoping to find here?
[Voice over.] For animals that can't adapt to climate change, it's going to be tough, to say the least. And when those animals help provide the food we eat, it's going to impact on us too. For David Brooks, it all starts with the humble beetle.
David Brooks: That is actually what we were looking for - it's a ground beetle.
Tom Heap: So why is it you're so interested in this beetle?
David Brooks: Well, I'm really interested in this whole group of beetles, specifically because they're very important in agriculture. And where they're important is: they're predatory insects, what we call carnivorous insects - they eat other insects - but the insects they eat are particularly pest species, so things like greenfly and slugs, so they're very important in terms of maintaining the sustainability of agriculture, in helping the farmer with his yields of the crops.
Tom Heap: I was going to say, they really are the farmer's friend, are they then, these beetles?
David Brooks: Very much so, yes, yeah.
Tom Heap: And what are you seeing, in terms of their numbers recently, do you think might be relevant for a climate change story?
David Brooks: What we're seeing overall is three quarters of the species that we've trapped, out of 68 species, are actually in decline. These beetles, different species, are very much adapted to the habitat that they're actually in.
Tom Heap: Aha.
David Brooks: So when that changes, then the climate can have adverse effects.
Tom Heap [voice over]: Numbers are declining, but this bug's a battler - he's survived shifts in the climate before. This time it's different, though. And the way we manage our countryside is partly to blame.
David Brooks: This particular species was around just after the Ice Age, and it's survived the Ice Age - various huge climatic events. The difference was that their habitat wasn't so denuded as it is now, and fragmented. So they can move around the landscape much more. Now, the habitat's become more fragmented, they've come under a lot more pressure through intensification of farming methods, and so forth - climate can have a bigger effect than it would have done in the past.
Tom Heap [voice over]: So, from beetles to birds to blossom, there's growing evidence that climate change is affecting us now. And are these just isolated cases, or is the impact more widespread?
Richard Betts [accompanying Tom Heap as they walk through the Met Office's Hadley Centre]: So this is the operations centre - it is the nerve centre of the Met Office weather forecasting activity.
Tom Heap [voice over]: At the Met Office, they don't just do weather forecasts. They look at climate change across the world. Richard Betts, a scientist here, helped write a major international report which says a wide range of plants and animals are being affected.
Richard Betts: So we're seeing the natural world responding to a changing climate, in the UK. We're also seeing that happening in other countries around the northern hemisphere, and also you could see it from the satellites as well - you can see trees coming into leaf earlier in the spring. Because these changes in the natural world are signs that the climate is changing, and in fact these are the clearest indicators of an impact of climate change.
Tom Heap: A lot of your information, though, and your understanding comes from models - talk me through what we've got here.
Richard Betts [displaying colour-coded temperature data on a computer monitor]: So this is showing temperature changes relative to the pre-industrial state, essentially - blues are colder, yellows and oranges, and reds later on, will be warmer than the pre-industrial state. You can see the different patterns of warming around the world, and as we get on to the end of the 21st century, we're getting these high levels of warming of 4 or 5 degrees, or more [the globe is now mostly a fiery yellow or orange, with the polar regions appearing red].
Tom Heap: We've been looking at the response of plants and animals - you know, it makes me wonder how they'll cope when the Earth might look like this.
Richard Betts: What we're seeing at the moment, and what we expect in the future, is change which is unusually fast.
Tom Heap: And therefore difficult for nature to adapt fast enough to keep up with?
Richard Betts: That's right. And in particular, if species are responding differently, at different rates, you'll get disruption of the ecosystems through these different rates of response. If you've got certain natural events tied to spring, if one species is moving forward by a week and another by two days, they come out of synchrony, so if they're depending on each other, their interdependency is potentially broken. So disrupting these ecosystems is what would be expected as a consequence of this.
Tom Heap [voice over]: So, botanists and bird and bug specialists do seem pretty convinced they're seeing some signs of nature responding to a change in climate. And whilst wildlife has adapted to shifting weather patterns before, if today's change is too rapid, it's feared some species could get left behind.