CaribJournal » Global Warming: Rising Global Temperatures Could Lead to More Diseases, Scientists say

CaribJournal » Global Warming: Rising Global Temperatures Could Lead to More Diseases, Scientists say

As the Earth's temperatures continue to rise, we can expect a signficant change in infectious disease patterns around the globe. Just exactly what those changes will be remains unclear, but scientists agree they will not be for the good.

"Environmental changes have always been associated with the appearance of new diseases or the arrival of old diseases in new places. With more changes, we can expect more surprises," says Stephen Morse of Columbia University, speaking on May 22, 2007, at the 107th General Meeting of the American Society for Microbiology in Toronto.

In its April 2007 report on the impacts of climate change, the Intergovernmental Panel on Climate Change (IPCC) warned that rising temperatures may result in "the altered spatial distribution of some infectious disease vectors," and will have "mixed effects, such as the decrease or increase of the range and transmission potential of malaria in Africa."

"Diseases carried by insects and ticks are likely to be affected by environmental changes because these creatures are themselves very sensitive to vegetation type, temperature, humidity etc. However, the direction of change – whether the diseases will increase or decrease – is much more difficult to predict, because disease transmission involves many factors, some of which will increase and some decrease with environmental change. A combination of historical disease records and present-day ground-based surveillance, remotely sensed (satellite) and other data, and good predictive models is needed to describe the past, explain the present and predict the future of vector-borne infectious diseases," says David Rogers of Oxford University, also speaking at the meeting.

One impact of rising global temperatures, though, can be fairly accurately predicted, says Morse. In the mountains of endemic areas, malaria is not transmitted above a certain altitude because temperatures are too cold to support mosquitoes. As temperatures rise, this malaria line will rise as well.

"One of the first indicators of rising global temperatures could be malaria climbing mountains," says Morse.

Another change could be the flu season. Influenza is a year-round event in the tropics. If the tropical airmass around the Earth's equator expands, as new areas lose their seasons they may also begin to see influenza year-round.

And extreme weather events will also lead to more disease, unless we are prepared. As the frequency, intensity, and duration of extreme weather events change, water supplies become more at risk, according Joan Rose of Michigan State University.

"Hurricanes, typhoons, tornados and just high intensity storms have exacerbated an aging drinking and wastewater infrastructure, enhanced the mixing of untreated sewage and water supplies, re-suspended pathogens from sediments and displaced large populations to temporary shelters. We are at greater risk than ever before of infectious disease associated with increasing extreme weather events," says Rose.

There will also be indirect effects of climate change on infectious disease as well. For instance, says Morse, the effect of global warming on agriculture could lead to significant changes in disease transmission and distribution.

"If agriculture in a particular area begins to fail due drought, more people will move into cities," says Morse. High population densities, especially in developing countries, are associated with an increased transmission of a variety of diseases including HIV, tuberculosis, respiratory diseases (such as influenza) and sexually transmitted diseases.

"I'm worried about climate change and agree that something needs to be done," says Morse. "Otherwise, we can hope our luck will hold out."

Whales In Hot Water: Global Warming's Effect On World's Largest Creatures

ScienceDaily: Whales In Hot Water: Global Warming's Effect On World's Largest Creatures

Whales, dolphins and porpoises (cetaceans) are facing increasing threats from climate change, according to a new report published by WWF and the Whale and Dolphin Conservation Society.

Beluga whales rely on polar, icy waters for their habitat and food resources. (Credit: WWF-Canon / Kevin Schafer)

The report "Whales in hot water?" examines the impacts on cetaceans including:

• Changes in sea temperature
• Declining salinity because of the melting of ice and increased rainfall
• Sea level rise
• Loss of icy polar habitats
• Decline of krill populations in key areas. Krill is a tiny shrimp-like marine animal that is dependent on sea ice and is the main source of food for many of the great whales.

"Whales, dolphins and porpoises have some capacity to adapt to their changing environment," said Mark Simmonds, International Director of Science at WCDS. "But the climate is now changing at such a fast pace that it is unclear to what extent whales and dolphins will be able to adjust, and we believe many populations to be very vulnerable to predicted changes."

Climate change impacts are currently greatest in the Arctic and the Antarctic. According to the report, cetaceans that rely on polar, icy waters for their habitat and food resources – such as belugas, narwhal, and bowhead whales – are likely to be dramatically affected by the reduction of sea ice cover.

As sea ice cover decreases there will be more human activities such as commercial shipping, oil, gas and mining exploration and development, and military activities in previously untouched areas of the Arctic.

"This will result in much greater risks from oil and chemical spills, worse acoustic disturbance and more collisions between whales and ships," said the lead author of the report, Wendy Elliott, from WWF's Global Species Program.

Other projected impacts of climate change listed in the report include: reduction of available habitat for several cetacean species unable to move into colder waters (e.g. river dolphins), the acidification of the oceans as they absorb growing quantities of CO ₂, an increased susceptibility of cetaceans to diseases, and reduced reproductive success, body condition and survival rates.

Climate change could also be the nail in the coffin for the last 300 or so endangered North Atlantic right whales, as the survival of their calves has been directly related to the effects of climate variability on prey abundance.

WCDS and WWF are urging governments to cut CO₂ global emissions by at least 50 percent by the middle of this century. The latest report of the Intergovernmental Panel on Climate Change showed it was possible to stop global warming if the world's emissions start to decline before 2015.

The two conservation organizations further call on the International Whaling Commission to facilitate research on future impacts of climate change on cetaceans, including supporting a special climate change workshop in the coming year, elaborate conservation and management plans in light of the climate change threat, and increase efforts and resources to fight other threats to cetaceans.

Butterflies: Harbingers of Climate Change (TreeHugger)

Butterflies: Harbingers of Climate Change (TreeHugger)

In a clear sign of the wider ramifications of climate change on some of the planet's wildlife, biologists in Britain have noted that at least 11 butterfly species made their earliest recorded appearances this year. Of the 59 resident and regular migrant species, 37 have already appeared and, besides for one species (the orange tip), have done so earlier than they would've a decade ago, according to Butterfly Conservation, a wildlife organization.

Some species have broken all records in the extent to which they have pushed forward their normal appearance dates: the Lulworth skipper, which usually makes its first appearance in the third week of June, was seen as early as April 28 while the speckled wood, which typically appears at the end of March, was observed in its Cornwall habitat on January 16, a record seven weeks ahead of schedule.

Overall, the Butterfly Conservation estimates that these butterfly species emerged more than four-and-a-half weeks earlier on average than they would've done ten years ago. The organization's officials are certain that climate change is linked to the early appearance of the majority of Britain's butterflies.

"Butterfly data, collected by hundreds of UK recorders, definitely points to climate change," Mr Warren said. "Species are not only emerging early, but several species are extending their geographic range northwards. The small skipper, the comma and the holly blue butterflies have all crossed the border into Scotland in the past few years, very probably as a result of the changing climate."

India, China, Brazil hold up climate change talks- Hindustan Times

India, China, Brazil hold up climate change talks- Hindustan Times

A demand by India, China, and Brazil that rich nations accept they are mainly responsible for global warming has held up progress at a key UN climate change conference in Bangkok, delegates said on Wednesday.

The three nations' insistence since the talks started on Monday that the developed world recognise their dominant role in climate change has stolen precious time meant for debate on how best to tackle global warming, they said.

"Progress is slow," one delegate from a European nation, who asked not to be identified said.

"Brazil, India and China are trying to put on the shoulders of industrialised nations the historic responsibility for greenhouse gas emissions, in order to clear their own emissions (of blame) and to protect themselves in any discussion."

At least 400 scientists and experts from about 120 countries are attending the week-long third session of the Intergovernmental Panel on Climate Change (IPCC), the UN's leading authority on global warming.

Their report, expected to be released at the end of their meeting on Friday, aims to lay out ways to reduce greenhouse gas emissions and prevent a climate catastrophe without seriously hurting the global economy.

But China has also insisted on specific figures, which lay the blame for global warming on rich nations, be inserted into the conclusions.

Various delegates said the demands, made by China but backed by India and Brazil, were not relevant to this week's meeting because it was meant to specifically look at ways to mitigate climate change. 

globeandmail.com: Climate change could put Canada's Arctic whales in hot water

globeandmail.com: Climate change could put Canada's Arctic whales in hot water

A new report says climate change could be putting Canada's Arctic whales in hot water.

The report, released Tuesday by the World Wildlife Fund, said global warming is likely having the same effect on whales that it's having on polar bears — changing the conditions under which they are adapted to live.

"It is unclear to what extent cetaceans will be able to adapt to the rate of climate change predicted in the near future," says the report.

"As temperatures increase, there are likely to be significant losses of polar 'specialist' species and a general shift of more temperate species towards the poles."

Previous research suggests the Arctic is warming at twice the rate of other parts of the globe. As well, the U.S. Snow and Ice Data Centre reports that sea ice already extends about 14 per cent less than it did in the '70s.

That could have serious implications for species such as beluga, a small white whale loved by the Inuit for its meat and blubber and by southern aquarium-goers for its smiley face, as well as narwhal, also hunted for food and renowned for the single long tusk growing out of its head.

Both whales are not only heavily dependent on the abundant life that blooms around the sea ice edge but also strongly tied to specific areas of it.

"Those two species are almost like robots," said Kristen Laidre, a marine biologist at the University of Washington who has just returned from a narwhal research trip to Greenland.

"They go to the same area year after year after year."

As climate change shifts everything from the extent of the ice cover to the time of spring breakup, no one knows how the whales will react.

"Would they move north with the sea ice? That's one of the big debatable questions," Ms. Laidre says.

Being at the right place at the right time is critical for all northern animals, and whales are no different.

"They're very much in rhythm with that system and exploit it," Ms. Laidre says. "If that (timing) changes, that's probably where the effects will be seen."

The report, entitled Whales In Hot Water?, also suggests that Arctic whales may face more competition for resources as warming oceans push whales north who would normally live in more temperate waters.

Dependable areas of year-round open water, called polynyas, could freeze over, trapping whales under the ice. As well, whales are likely to suffer from increased noise and chemical pollution as Arctic waters become busier shipping routes.

Belugas and bowheads have been seen to flee ships approaching within 35 kilometres.

"It is expected that the opening of the Northwest Passage will have a strong negative effect on cetaceans in the area, particularly when the synergistic effects of these human activities and the climate-change induced shifts in the ecosystem are considered," the report says.

Ms. Laidre says it's hard to predict the effects of climate change on Arctic whales because so little is known about them. Arctic research is both expensive and logistically difficult.

But Pete Ewins of the World Wildlife Fund says the Arctic whales face the same plight as that of polar bears. The sea ice that both shelters and feeds them is changing and — mostly — shrinking.

"The steps you need to take require you to not only turn down the (carbon dioxide) but also to be cautious and manage other activities," he said, noting that military, industrial and tourist activities in formerly silent Arctic waters are all increasing with the melting ice.

Species such as whales and polar bears are not only pop-culture icons, but also good indicators of the health of an ecosystem, said Mr. Ewins.

"They are flagships of the marine systems," he said.

"If you get it right for Arctic whales, then numerous other species down the food chain would benefit."

AlterNet: Environment: Carbon Emissions Exceed Highest Assumptions Used in Climate Change Studies

AlterNet: Environment: Carbon Emissions Exceed Highest Assumptions Used in Climate Change Studies

While global warming deniers argue that most climatologists are alarmists, CO2 emissions in the past few years have exceeded the levels used in scientists' models -- signaling even more cause for concern.

Global emissions of carbon dioxide are growing at a faster clip than the highest rates used in recent key UN reports.

CO2 emissions from cars, factories, and power plants grew at an annual rate of 1.1 percent during the 1990s, according to the Global Carbon Project, which is a data clearinghouse set up in 2001 as a cooperative effort among UN-related groups and other scientific organizations. But from 2000 to 2004, CO2 emissions rates almost tripled to 3 percent a year - higher than any rate used in emissions scenarios for the reports by the Intergovernmental Panel on Climate Change (IPCC).

If the higher rate represents more than a blip, stabilizing emissions by 2100 will be more difficult than the latest UN reports indicate, some analysts say. And to avoid the most serious effects of global warming, significant cuts in CO2 emissions must begin sooner than the IPCC reports suggest. At the moment, no region of the world is "decarbonizing its energy supply," the analysis says.

The Global Carbon Project's calculations should be viewed with caution, says Michael Oppenheimer, a climate-policy specialist at Princeton University in New Jersey. Economies have been recovering from a recession at the turn of the millennium. And a spike in natural-gas prices - of uncertain duration - has given coal a second wind in developed countries. These short-term factors have probably contributed to the growth in emissions rates, he says.

Yet longer-term forces may be at play to sustain the high emissions rates. For instance, "There is concern among many experts that factors such as China's continued, very rapid coal-based growth may not be a blip that would turn around," he says.

The analysis is the Global Carbon Project's first cut at an annual effort to report on trends in CO2 emissions and the factors contributing to them, says Christopher Field, a scientist with the Carnegie Institution of Washington.

"We're trying to figure out a small set of numbers that give people a clear picture" of what's happening, says Dr. Field, a member of the Global Carbon Project's science steering committee and a co-author of the analysis, which appears in Monday's edition of the Proceedings of the National Academy of Sciences.

The analysis comes at a time when negotiators for the G-8 group of leading industrial countries have been trying to work out the wording of a section on climate change, proposed for the final declaration at the group's meeting in Germany next month. Last week, US negotiators red-penciled key portions, severely weakening the statement.

The analysis also comes as countries prepare for a new round of UN-sponsored climate talks, scheduled for December in Bali. Negotiators are trying to establish a track for talks that would provide a seamless transition between the 1997 Kyoto Protocol's first reporting period, which runs from 2008 to 2012, and a new international regime to combat global warming that would follow - one in which developing countries would start taking an active role.

So far, developing countries account for only about 23 percent of emissions accumulated since the start of the Industrial Revolution. But they also account for 73 percent of the global emissions growth in 2004. This has been largely driven by China's explosive growth.

In trying to figure out how emissions-reductions burdens are apportioned, which number should dominate?

"There are very difficult discussions at the international level that must be dealt with," acknowledges Andrew Weaver, a climate scientist at the University of Victoria in British Columbia and chief editor of the Journal of Climate.

In broad terms, growing population and rising per capita economic growth have fueled the increase in emissions rates, Field explains. In addition, he says, two trends appear to be taking hold. Globally, the amount of energy used per unit of gross domestic product is leveling or increasing after years of decline. This could mean that gains in energy efficiency are slowing. It could also mean that the growth of heavy industry in developing countries is offsetting the shift to less energy-intensive activities in develped countries.

Second, the energy sources that countries are using are more carbon-intensive than in the past.

The Global Carbon Project study held two surprises for everyone involved, Field says. "The first was how big the change in emissions rates is between the 1990s and after 2000." The other: "The number on carbon intensity of the world economy is going up."

Meanwhile, scientists are noting that some of the natural "sinks" for the CO2 that humans are pumping into the atmosphere are becoming less efficient at absorbing emissions. Natural sinks – the oceans and plants on land – have been absorbing about half the emissions that humans produce. But the Southern Ocean, which serves as a moat around Antarctica, is losing its ability to take up additional CO2, reports an international team of researchers in the journal Science this week. The team attributes the change to patterns of higher winds, traceable to ozone depletion high above Antarctica, and to global warming.

"There's been a lot of discussion about whether the scenarios that climate modelers have used to characterize possible futures are biased toward the high end or the low end," Field adds. "I was surprised to see that the trajectory of emissions since 2000 now looks like it's running higher than the highest scenarios climate modelers are using."

If so, it wouldn't be the first time. Recently published research has shown that Arctic ice is disappearing faster than models have suggested.

Despite the relatively short period showing an increase in emissions growth rates, the Global Carbon Project's report "is very disturbing," Dr. Weaver says. "As a global society, we need to get down to a level of 90 percent reductions by 2050" to have a decent chance of warding off the strongest effects of global warming.

If this study is correct, "to get there we have to turn this corner much faster than it looks like we're doing," he says.