Stories tagged global warming
Tags : Researchers at Duke University have discovered that poison ivy grows bigger and faster--and makes more of its itch-producing chemical--as carbon dioxide levels in the atmosphere rise. Carbon dioxide is a greenhouse gas and the major culprit suspected in global warming. Time to buy stock in Calamine?...
Monarch butterfly: Courtesy Matt Stratton
The number of butterflies migrating through California has dropped to a forty year low, according to researchers at the University of California, Davis. One-half of the usual species of butterflies have not appeared this season, and other species have been observed in very low numbers. Climate change related to global warming and habitat destruction may be the cause.
Global warming is the increase in the Earth’s average temperature over recent decades primarily attributable to human activities.
Habitat destruction is a change in land use in which one habitat is replaced with another. The plants and animals which previously used the site are destroyed or displaced in the process.
A mild winter in Northern California has caused many species to not end their winter dormancy at the right time. This means that many butterflies emerged too late in the season. The proper climate for breeding was disrupted by a wet spring.
In Southern California, an unusually dry desert left little food for caterpillars of some species to feed on. A late snow in the Sierra Nevada may have killed many insects used for food.
Some species of butterflies that breed several times a year may rebound from these events, but for other species the effects may be devastating for up to a decade.
Read the original press release here.
Global warming has been in the news a lot lately. First, 60 scientists signed a petition asking the Canadian Prime Minister to open a scientific debate on the Kyoto Treaty. (The Kyoto Treaty is an international agreement to reduce global warming by reducing industrial emissions. Some people think the treaty has too many loopholes, and even if the loopholes were closed, it would still not be effective. The US has not signed the treaty. Science Buzz has had its own Kyoto debate.)
The scientists argue:
Much of the billions of dollars earmarked for implementation of the protocol in Canada will be squandered without a proper assessment of recent developments in climate science. …
It may be many years yet before we properly understand the Earth's climate system. Nevertheless, significant advances have been made since the protocol was created, many of which are taking us away from a concern about increasing greenhouse gases. …
The new Canadian government's commitment to reducing air, land and water pollution is commendable, but allocating funds to "stopping climate change" would be irrational. We need to continue intensive research into the real causes of climate change and help our most vulnerable citizens adapt to whatever nature throws at us next.
Next, a climate researcher in Australia has looked at current climate data and found that global temperatures have been holding steady since 1998:
Two simple graphs provide needed context, and exemplify the dynamic, fluctuating nature of climate change. The first is a temperature curve for the last six million years, which shows a three-million year period when it was several degrees warmer than today, followed by a three-million year cooling trend which was accompanied by an increase in the magnitude of the pervasive, higher frequency, cold and warm climate cycles. During the last three such warm (interglacial) periods, temperatures at high latitudes were as much as 5 degrees warmer than today's. The second graph shows the average global temperature over the last eight years, which has proved to be a period of stasis.
Finally, an atmospheric scientist at the Massachusetts Institute of Technology argues that there is a vicious circle between climate scientists who find evidence of global warming; environmental activists who use those findings to advance their cause; and policy makers who respond to the activists by giving more money to… the climate scientists.
(He also claims that scientists who raise doubts about global warming and human impact on climate are sometimes shut out of the debate. Science Buzz has had it’s own discussion on disagreements within the scientific community.)
So, what to make of all of this? I think the MIT professor said it well:
[L]et's start where there is agreement. The public, press and policy makers have been repeatedly told that three claims have widespread scientific support: Global temperature has risen about a degree since the late 19th century; levels of CO2 in the atmosphere have increased by about 30% over the same period; and CO2 should contribute to future warming. These claims are true. However, what the public fails to grasp is that the claims neither constitute support for alarm nor establish man's responsibility for the small amount of warming that has occurred.
This all illustrates the dynamic interaction between science and politics. Science is about facts. Politics is about opinion – what should we do in the fact of those facts? But the distinction is not always clear. Science influences political debate; and political decisions influence what science gets support. The best thing to do is to keep an open mind, remembering that most people have some sort of agenda, and that new information is coming out all the time.
(The Science Museum of Minnesota did an exhibit on global warming. You can find the website here.)
There is often a tension between the scientists who study a subject and the people who live in the area of interest.
Recently in Alaska, scientists have began using the oral histories of native Alaskans as another source of evidence for climate change.
Residents of Alaska have been saying that the 1970's were a turning point as far as noticing changes in weather patterns and conditions.
Maggie Attila, from Galena, stated, "The last couple of years has been really crazy. It is kind of scary when the wind comes up at the wrong time and we have rain in the winter."
Do you think that Alaskan residents are a useful source of information about climate change? Does the Attila's statement make you think of the past few years of Minnesotan weather?
We had an earlier thread on global warming here. Now, just to complicate matters, a group of researchers is arguing that warmer global temperatures are actually a good thing.
"If you could vote for a change in climate, you would always want a warmer one," says Philip Stott, emeritus professor of biogeography at the University of London. "Cold is nearly always worse for everything - the economy, agriculture, disease, biodiversity".
Other scientists dispute these claims, and point to other evidence.
And that's exactly how science works -- you make a hypothesis, then you test it with an experiment or compare it to evidence to see if it stands up.
The problems is, both sides of the global warming debate have made some pretty outrageous statements -- which leaves us citizens in the middle not knowing who to believe. And that can be dangerous: if a group keeps making extreme claims that turn out to be wrong, who will believe them when they're right?
What do YOU think? Is the debate over global warming helpful, or confusing? What, if anything, should we be doing about it?
Last year's hurricane season sprouted an unusually high number of tropical storms — 15 in all. Some folks have blamed global climate change. But researchers at the National Oceanic and Atmospheric Administration say the increase is perfectly natural. Hurricanes follow a natural cycle, peaking every 15 to 40 years, then dropping back and becoming rarer again.
Other researchers disagree. They say rising global temperatures lead to warmer water, a key ingredient in forming hurricanes.
Few people doubt that the Earth's climate is growing warmer. But how much of that is just a natural cycle, and how much of it is caused by human activity? And what will all the effects of this change be? No one knows for sure. Meanwhile the debate, and research, go on.
