Over Easy: Bringing You Science on a Monday
(Picture courtesy of Amanda Graham at flickr.com.)
Regrettably, BoxTurtle has had to be away on family matters, so to host readers hoping for a dose of science on their Monday morning, I’ve put together this brief post and hope this will tide you over. We will all be glad for BT to return and look forward to his in depth reports soon.
Tracking the volume of sea ice at the poles has provided a stressful situation as we’ve seen it diminish, and life at those poles change for its varied life forms that include the much stressed polar bear. This year, for a change, the ice pack in the Arctic has benefited from two cooler than usual summers, and has maintained its volume.
“What we see is the volume going down and down, but then, because of a relatively cool summer, coming back up to form a new high stand,” said Rachel Tilling from the UK’s Nerc Centre for Polar Observation and Modelling (CPOM) at University College London (UCL).
“So, what may be occurring here is a decline that looks a bit like a sawtooth, where we can lose volume but then recover some of it if there happens to be a shorter melt season one year,” she told BBC News.
“You might think, for example, that wind conditions would be important because they can pile the ice up and make it less susceptible to melting, while at the same time exposing more water to freeze,” the University College London researcher explained.
“But we’ve looked at this and other factors, and by far the highest correlation is with temperature-driven melting.”
The polar bear population has suffered from the diminishing ice pack, and has declined as the bears could not swim increasing distances to hunt.
Climate change is the primary threat to polar bears, melting the sea ice that is their critical habitat and reducing their access to prey. By 2070, the study found, over 80% of the archipelago’s ice could break up in July, forcing pregnant females to retreat to land early. And although thin ice is better habitat for seals, the bears’ main prey, it may simply not persist long enough to allow the polar bears sufficient hunting opportunities.
The loss of its unique species makes the world a sadder place. For this year, the polar bear and related species have not lost further ground. Since 2002, melt has diminished the ice pack to hazardous minimums. Climate and water quality loss have greatly diminished the number of species and variety of life.
Within the next 30 years as many as half of the species on the earth could die in one of the fastest mass extinctions in the planet’s 4.5 billion years history. Dr Leakey, author of “The Sixth Extinction,” believes that 50% of the earth’s species will vanish within 100 years and that such a dramatic and overwhelming mass extinction threatens the entire, complex fabric of life, including Homo sapiens, (the species responsible for the crisis.)
The problem is not just the loss of species. There is also the loss of the genetic diversity within species, as well as the loss of diversity of different types of ecosystems ,which can contribute to or hasten whole species extinction. Preserving the wider gene pool diversity in subdivisions of species, such as subspecies and populations, offers the raw material for the evolution of new species in the future.
“Every day, an estimated 100 plant and animal species are lost to deforestation” . . . “A conservative estimate of the current extinction rate indicates that about 27,000 species a year are being lost.” National Wildlife Federation
There is hope that nations of the world will act to end the loss of quality of life we all suffer. Acting in concert, the world’s nations have come to such an agreement in Lima, Peru.
International negotiators at the Lima climate change talks have agreed on a plan to fight global warming that would for the first time commit all countries to cutting their greenhouse gas emissions.
(Picture courtesy of Cheryl at flickr.com.)