Airdate: May 07, 2001
Scientist: David Inouye
Early Spring: Harbingers
A broad range of species of plants are blooming up to 46 days earlier now than they did three decades ago. The reason, biologists say, is global climate change.
Early Spring - Harbingers
Music; Ambience: birds, dawn chorus, East coast
JM: Everyone has their own favorite harbinger of spring. For some it might be the first robin, for others a glimpse of an early crocus. Scientists are telling us that these events are happening earlier each year - more signs that the earth's temperature is warming. I'm Jim Metzner, and this is the Pulse of the Planet. David Inouye is director of the graduate program of conservation biology at the University of Maryland.
DI: "There are a number of signs that global warming is occurring. The seasonal timing of events is probably the best way that the general public would notice how climate change is affecting plants and animals around us. If you've been keeping long term records as people have in Great Britain, and now to a growing degree here in North America, of when the first bird arrived, when the first insects were seen, when the first flower opened, when the first buds broke - people have noticed that these events are happening earlier and earlier, over the last few decades, and I think that's probably some of the best evidence that global warming is effecting the plants and animals around us. There's a group of biologists at the Smithsonian's Natural History Museum, in the botany department, that have been looking for the last twenty-nine years at what was the first date of flowering for about a hundred different species in this area and they have found that the eighty-nine species which are flowering earlier now than they used to, are, on average, flowering about four and a half days earlier. The range for individual species is all the way up to forty-six days earlier now, than these plants came into bloom twenty-nine years ago. So, even here in the Washington D.C. area, it's quite easy, if you have that kind of a record, to pick up on these changes that we can attribute to global climate change, to global warming in particular."
JM: In future programs we'll hear more about the signs of spring arriving early. To hear more about our new CD, please visit pulseplanet.com. Pulse of the Planet is presented by the National Science Foundation. I'm Jim Metzner.