RFE/RL: What can you tell us about the projection that the Met Office has made for the global weather in 2007?
David Parker: The projection is for the global average temperature to be 0.54 degrees Celsius above the 1961-1990 average. It's not a projection for any particular location. The reason that a warm year is being forecast -- 0.54 would be slightly warmer than the previous record of 0.52 in 1998 -- is that there is a moderate strength El Nino warming event in the equatorial eastern Pacific. Another reason is the ongoing increases in greenhouse gases.
RFE/RL: Could you explain, for a layperson, just what El Nino is?
Parker: El Nino is a natural warming of the eastern Pacific Ocean. It results from a combination of winds and ocean currents. It happens irregularly, and there was a big one back in 1978 and there have only been some weak ones since then. The El Nino is, really, a change of ocean currents, especially near South America. It interacts with the air to alter the rainfall in some parts of the tropics, in particular.
RFE/RL: So how certain are you that 2007 will be the hottest year on record?
Parker: Our calculations have uncertainty estimates. It means that we accord only a 60 percent probability that 2007 will be as warm or warmer than 1998.
RFE/RL: Does the El Nino phenomenon affect certain parts of the globe more than others?
Parker: It does. It particularly affects the tropics and the Americas. There are some possible affects on Europe, but these are more difficult to trace and they're a matter of ongoing research.
RFE/RL: So the fact that continental Europe, for example, has been experiencing a very mild winter so far can't really be blamed on El Nino?
Parker: Not that in particular. There is some tendency for the second half of the winter to be colder in Europe when there's El Nino. So there is some tendency that there might be, by around February or March, some more cold weather and some more snow. That's not a very strong relationship but the relationship is there.
RFE/RL: When does the El Nino effect begin to diminish?
Parker: The El Nino tends to last to about the middle of the year. But the global temperature tends to lag behind the El Nino. So when there's been an El Nino from end of summer 2006 to beginning of summer 2007, for example, then the warmth in the globe would tend to last from the very end of 2006 right through to nearly the end of 2007, which is one reason why we expect it to be a warm year.
RFE/RL: Is it natural to expect more extreme-weather phenomena this year -- such as floods, droughts, hurricanes -- as a result of a very warm year?
Parker: There seems to be a tendency to have more extremes with global warming. Obviously, if the temperature of the world goes up, then warm extremes become more likely and cold extremes become less likely. Hurricanes depend on a lot more than just the temperature; they depend on the behavior of the winds throughout the atmosphere. And it's not very easy to say whether in the long term there will be an increase in hurricanes. When there's an El Nino that tends to dampen down the hurricanes in the Caribbean, which is why we had fewer in 2006 than in 2005. But I'm not yet ready to issue a forecast for the hurricanes of 2007.
View a photo gallery summarizing some key findings of the Stern report on the economic costs of global warming (epa)
THE STERN REPORT: In October, former World Bank chief economist Sir Nicholas Stern issued a 700-page report on the economic impact of global warming. The report, which was commissioned by the British government, estimates that climate change could cost between 5 and 20 percent of global GDP by the end of the century....(more)