Science and the EnvironmentsSubscribe to Science and the Environments

New calculations reveal that the number of species on Earth is likely to be in the order of several million rather than 10’s of millions. The findings, from a University of Melbourne-led study, are based on a new method of estimating tropical insect species—the largest and one of the most difficult groups on the planet to study—having significant implications for conservation efforts.

Melting sea ice has been shown to be a major cause of warming in the Arctic according to a University of Melbourne study. 

Findings published in Nature today reveal the rapid melting of sea ice has dramatically increased the levels of warming in the region in the last two decades.

Lead author Dr James Screen of the School of Earth Sciences at the University of Melbourne says the increased Arctic warming was due to a positive feedback between sea ice melting and atmospheric warming.

“The sea ice acts like a shiny lid on the Arctic Ocean. When it is heated, it reflects most of the incoming sunlight back into space. When the sea ice melts, more heat is absorbed by the water. The warmer water then heats the atmosphere above it.“

“What we found is this feedback system has warmed the atmosphere at a faster rate than it would otherwise,” he says.

Using the latest observational data from the European Centre for Medium-Range Weather Forecasting, Dr Screen was able to uncover a distinctive pattern of warming, highly consistent with the loss of sea ice.

“In the study, we investigated at what level in the atmosphere the warming was occurring. What stood out was how highly concentrated the warming was in the lower atmosphere than anywhere else. I was then able to make the link between the warming pattern and the melting of the sea ice.”

The findings question previous thought that warmer air transported from lower latitudes toward the pole, or changes in cloud cover, are the primary causes of enhanced Arctic warming.

Dr Screen says prior to this latest data set being available there was a lot of contrasting information and inconclusive data.

“This current data has provided a fuller picture of what is happening in the region,” he says.

Over the past 20 years the Arctic has experienced the fastest warming of any region on the planet. Researchers around the globe have been trying to find out why.

Researchers say warming has been partly caused by increasing human greenhouse gas emissions. At the same time, the Arctic sea ice has been declining dramatically. In summer 2007 the Arctic had the lowest sea ice cover on record. Since then levels have recovered a little but the long-term trend is still one of decreasing ice.

Professor Ian Simmonds, of the University’s School of Earth Sciences and coauthor on the paper says the findings are significant.

“It was previously thought that loss of sea ice could cause further warming. Now we have confirmation this is already happening.”

Melting sea ice has been shown to be a major cause of warming in the Arctic according to a University of Melbourne study.

The teaching program of the University of Melbourne’s Office for Environmental Programs has been announced as a finalist in the Tertiary Education category of the 2010 Premier’s Sustainability Awards, and is in the running for the coveted Premier’s Recognition Award.

University of Melbourne vets are warning that owners with unvaccinated dogs or dogs with uncertain vaccination histories should visit their local clinic immediately to protect their pets against the potentially deadly Canine Parvovirus. Melbourne veterinary clinics have seen a sharp rise in cases of Canine Parvovirus, a severe gastrointestinal infection which can be fatal for small and elderly dogs.

The groundbreaking book ‘Worlds in Transition’, which explores democratic decision-making from local to planetary scale, will be launched at the University of Melbourne today. Co-authors Professor Jim Falk from the University of Melbourne and Professor Joseph Camilleri, from La Trobe University, have been praised for their work, providing ‘insights into the perils of our era’ and ‘issuing a clarion call for a system of multi-tiered governance to address them.’

The University of Melbourne has played a key role in dating a new species of human fossil found in South Africa.

Key contributors to climate change policy making in Australia will reflect on their experiences and point to the lessons that can be learnt at a forum at the University of Melbourne on Tuesday 30 March.

Internationally recognised computational scientist Professor Peter R Taylor has been appointed as the Director of the University of Melbourne led Victorian Life Sciences Computation Initiative (VLSCI).

Butterflies are emerging in spring over 10 days earlier than they did 65 years ago, a shift that has been linked to regional human-induced climate change in a University of Melbourne- led study. The work reveals for the first time, a causal link between increasing greenhouse gases, regional warming and the change in timing of a natural event.

Pages