Source: BBC Radio 4: PM
URL: N/A
Date: 16/01/2015
Event: Gavin Schmidt: "we're pretty confident that 2014 was in fact the warmest year"
Credit: BBC Radio 4: PM
People:
Eddie Mair: The US space agency NASA and another American organisation the National Oceanic and Atmospheric Administration both say that 2014 was the warmest year on record, on planet Earth. They say global temperatures were 0.68 Celsius above the long-term average. Gavin Schmidt is Director of the Goddard Institute of Space Studies, the branch of NASA that conducted this study. How do you measure the Earth's temperature?
Gavin Schmidt: That's a great question, and thanks for having me on. Um, basically we're collating information that comes from weather services around the world, including the UK Met Office, but also measurements from ships, from buoys floating in the ocean, from, you know, stations in Antarctica and in the High Arctic. And then we take that data, we put it all together, we try and correct for some of the obvious biases in those datasets, and make an estimate of the global mean temperature anomaly. And, as you said, this year comes out to be the record warmest year in our 135-year record.
Eddie Mair: And is that just a quirk?
Gavin Schmidt: No, no, it's part of a pattern - the last few record years were 2010, 2005, 1998, you'll see they're all towards the end. We - the planet, in fact, is warming and those long-term trends are almost certainly associated with the increases in greenhouse gases, particularly carbon dioxide that humans have been putting into the atmosphere.
Eddie Mair: What do the stats tell you about whether or not the planet's getting warmer more quickly?
Gavin Schmidt: Um, it's been getting warmer more quickly over the last 30 or 40 years, compared to the previous half century, and if you look at the projections, going forward, we do expect it to accelerate further towards the middle and end of this century. But that depends a little bit on the actual technology, economic changes that society decides to implement. It's not something that you can see in short-term records - you can't say, you know, that the five years it's warming up faster than the previous five years, that's very affected by weather, by noise in the ocean system, particularly.
Eddie Mair: And, just briefly, are your stats solid? Are you sure about them?
Gavin Schmidt: So we do try and make sure that they are indeed solid - we take into account a lot of the structural uncertainties, you know, places where we're missing data or where there's records that might not be perfect, for whatever reason. But we're pretty confident that 2014 was in fact the warmest year - not, it's not completely unequivocal but it's very likely - but the most important thing is not one single year but it's the long-term trends, those are very, very solid indeed.
Eddie Mair: Thank you Gavin Schmidt, Director of the Goddard Institute of Space Studies.