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The "canary in the coalmine" for all of these shifts is the polar oceans, said Oscar Schofield, an oceanographer at Rutgers University in Newark, New Jersey and a co-author of the second review, which focuses on changes at the West Antarctic Peninsula. There, the authors found, temperatures have increased by 6 degrees Celsius in the past 50 years, more than five times the average change worldwide. Phytoplankton blooms are down 12 percent overall. Krill populations — important food for whales, penguins, fish and other large animals — are plummeting, with jellyfish-like organisms called salps, which don't make as good a meal, taking their place.

Above the surface, the polar Adélie penguin population has gone from tens of thousands of breeding pairs to just a few thousand, Schofield said. Temperate species of penguin like the Chinstrap and Gintoo are moving into the Adélie’s old turf. Particularly shocking, Schofield said, is how rapidly these changes are occurring. "It's not like it's happening over hundreds of years," he said. "It's happening over decades."

When plant plankton plummet — like they do during El Nino climate cycles_ sea birds and marine mammals starve and die in huge numbers, experts said.

Worm said when the surface of the ocean gets warmer, the warm water at the top doesn't mix as easily with the cooler water below. That makes it tougher for the plant plankton which are light and often live near the ocean surface to get nutrients in deeper, cooler water. It also matches other global warming trends, with the biggest effects at the poles and around the equator.

Phytoplankton are microscopic marine organisms capable of photosynthesis, just like terrestrial plants. They float in the upper layers of the oceans, provide much of the oxygen we breathe and account for about half of the total organic matter on Earth. A 40 per cent decline would represent a massive change to the global biosphere."If this holds up, something really serious is underway and has been underway for decades. I've been trying to think of a biological change that's bigger than this and I can't think of one," said marine biologist Boris Worm of Canada's Dalhousie University in Halifax, Nova Scotia. He said: "If real, it means that the marine ecosystem today looks very different to what it was a few decades ago and a lot of this change is happening way out in the open, blue ocean where we cannot see it. I'm concerned about this finding."The researchers studied phytoplankton records going back to 1899 when the measure of how much of the green chlorophyll pigment of phytoplankton was present in the upper ocean was monitored regularly. The scientists analysed about half a million measurements taken over the past century in 10 ocean regions, as well as measurements recorded by satellite.They found that phytoplankton had declined significantly in all but two of the ocean regions at an average global rate of about 1 per cent per year, most of which since the mid 20th Century. They found that this decline correlated with a corresponding rise in sea-surface temperatures – although they cannot prove that warmer oceans caused the decline.The study, published in the journal Nature, is the first analysis of its kind and deliberately used data gathered over such a long period of time to eliminate the sort of natural fluctuations in phytoplankton that are known to occur from one decade to the next due to normal oscillations in ocean temperatures, Dr Worm said. "Phytoplankton are a critical part of our planetary life support system. They produce half of the oxygen we breathe, draw down surface CO2 and ultimately support all of our fishes." he said.But some scientists have warned that the Dalhousie University study may not present a realistic picture of the true state of marine plantlife given that phytoplankton is subject to wide, natural fluctuations."Its an important observation and it's consistent with other observations, but the overall trend can be overinterpreted because of the masking effect of natural variations," said Manuel Barange of the Plymouth Marine Laboratory and a phytoplankton expert.

However, the Dalhousie scientists behind the three-year study said they have taken the natural oscillations of ocean temperatures into account and the overall conclusion of a 40 per cent decline in phytoplankton over the past century still holds true. "Phytoplankton are the basis of life in the oceans and are essential in maintaining the health of the oceans so we should be concerned about its decline."It's a very robust finding and we're very confident of it," said Daniel Boyce, the lead author of the study."Phytoplankton is the fuel on which marine ecosystems run. A decline of phytoplankton affects everything up the food chain, including humans," Dr Boyce said.

Phytoplankton is affected by the amount of nutrients the well up from the bottom of the oceans. In the North Atlantic phytoplankton "blooms" naturally in spring and autumn when ocean storms bring nutrients to the surface. One effect of rising sea temperatures has been to make the water column of some regions nearer the equator more stratified, with warmer water sitting on colder layers of water, making it more difficult for nutrients to reach the phytoplankton at the sea surface.Warmer seas in tropical regions are also known to have a direct effect on limiting the growth of phytoplankton.

Migration is dwindling worldwide, Middleton says, and preserving some of the last large mammal migrations in North America has become a key conservation concern. Satellite images of where the elk roam now suggest what’s gone wrong with their migration, Middleton reported June 14 at the annual meeting of the American Society of Mammalogists. Images show that the period when grasslands are thriving and green with prime nutrition for grazers shrank by 40 percent between 1989 and 2009, he said. This premature grassland brownout fits with weather station data showing that over the past 21 years, the average July temperature in the migrants’ high-elevation summer range has risen more than 4 degrees Celsius, Middleton said. On top of that, nearly a decade of drought worse than the Dust Bowl dry-out has parched the Yellowstone region. In contrast, satellite images show little change in the greening of vegetation at the lower elevation, Middleton said. Elk remaining there not only have a more stable summer food source, but can nip over to some scattered agricultural outfits to take advantage of irrigated vegetation.

At the RSPB’s Orkney reserve, many kittiwake nests have been found abandoned. Arctic terns have also struggled in the Northern Isles, and failed to breed significantly this year. Gilbert said: “The most likely cause is a lack of food, especially for terns and kittiwakes, which feed on sandeels. “Worryingly, it looks like this problem is being driven by climate change affecting the marine ecosystem from the bottom up.”

Although herring gulls are among the most commonly encountered birds in Scottish towns and cities, particularly in coastal areas, they were added to the RSPB’s “red list” of at-risk species last year. The latest 43% decline in their numbers means an overall 25-year fall of at least 70%.

The havoc has brought total economic losses in the nine provinces to 14.5 billion yuan (€1.7 billion), and affected 535,500 hectares of crops, further blighting food supply in the region. The conditions have also led to the collapse of 68,000 houses.

The meteorological bureau was forecasting more thunderstorms overnight and it was expecting rainfall of 100-180 millimetres in many areas, rising to over 200 millimetres in others.

“The scope and intensity of the rain have increased,” the office said on its website yesterday.This is effectively three times the usual level of rain in the region.Climate change has meant that each year the flooding gets worse, while the droughts are also worsening.

Parmesan and some colleagues also did a study of 57 European species that showed two-thirds were moving northward. Research shows many species move northward because of changes in the growth pattern of plants the butterfly relies on for food.

Butterflies that already live at high altitudes or in northerly sites are the most likely to be in serious trouble, Parmesan said."What we're seeing at the highest elevations is the species with nowhere to go are essentially evaporating off the tops of those mountains and we're losing those species," said Jeremy Kerr, associate professor of biology at the University of Ottawa, who has also studied the insects."Butterflies are this kind of canary in the coal mine that may be useful guides for what other species will eventually do and the pressures that other species, or species groups, may face," Kerr said.

Some early evidence suggests that more acidic water in Hood Canal is brought to the surface during storms, Dewey said. Unlike the ocean hatcheries, where acidity is linked directly to oyster mortality, there may be other factors at play in Hood Canal. “We have some very good scientists working on this,” he said. Oyster hatcheries may be able to adjust their intake water or add chemicals to help the larvae survive, Dewey said, but oysters in the wild are another story. Hood Canal has always been known for its abundant natural production, but that could be changing. Worse, numerous other shelled organisms — including zooplankton at the base of the food web and the many filter feeders that clean the waters — may be affected by the increasing acidity.

"Climate change is happening at a much greater and accelerated pace than we ever expected 30 years ago," said Richard Leopold, director of the Iowa Department of Natural Resources. Huge floods in 2008, which left the state's second-biggest city, Cedar Rapids, with massive downtown destruction, intensified the debate, with a new set of recommendations coming from a state panel by the end of the year. "If we decide as a state to significantly reduce greenhouse gas emissions in a hurry, we can actually do it," said Sen. Rob Hogg, a Democrat from Cedar Rapids. "There are a lot of things we can do for no cost, and others we can do for very little cost."

Summer storms already can be more intense, and the Midwest has fought to avoid major flooding this year.

The records Takle analysed showed Iowa averages five more frost-free days a year than in 1950. But that doesn't mean more time to grow crops, because of changes in temperature and precipitation patterns. Generally, Iowa now has warmer winters, but fewer extremely hot summer days. Overall, the Midwest is expected to warm through the middle of the century, but not as much as other parts of the country.

The marmots may not enjoy a permanent population boom. Ozgul says that his team is on the lookout for longer-term effects, such as drought-induced food shortages or predation by coyotes and foxes, which might check the population. "Most ecological studies last 2–3 years, the fieldwork of a graduate student, but these animals live 14 years. If you were to study the effect of climate change [a typical, short-term study] would tell us nothing," he says.