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In their overview of shifting climate in the region, Overpeck and Udall cite published findings of prevalent signs of change: rising temperatures, earlier snowmelt, northward-shifting winter storms, increasing precipitation intensity and flooding, record-setting drought, plummeting Colorado River reservoir storage, widespread vegetation mortality and more large wildfires. "The West, and especially the Southwest, is leading the nation in climate change – warming, drying, less late-winter snowpack and drought – as well as the impacts of this change," said Overpeck, a UA professor of geosciences and atmospheric sciences and co-director of the Institute of the Environment. In the past 10 years, temperatures in almost all areas in western North America have surpassed the 20th century average, many by more than 1 or even 2 degrees Fahrenheit. The warming has decreased late-season snowpack, which serves as a water reservoir, as well as the annual flow of the Colorado River, the researchers said.

Those reductions, combined with the worst drought observed since 1900, haven't helped matters; water storage in Lakes Powell and Mead, the largest southwestern water reservoirs, fell nearly 50 percent between 1999 and 2004 and has not risen significantly since.

In addition to water, vegetation is feeling the effects of climate change. Work by UA's David Breshears and colleagues have already showed that more than 1 million hectares of piñon pine have died in the Southwest in the last few decades from a lethal combination of record-high temperatures and uncommonly severe drought. In addition, the frequency of large wildfires has increased as snowpack has decreased.

Turbulent weather blows into the Southwest

According to many scientists, our atmospheric system is in such a “hydrologic cycle” with water, vapor and energy responding to the increase in heat from the Earth just like a pot of water on the stove. And this boiling point has made for increasingly windy years around the Four Corners

“Climate models indicate that global warming could be responsible for our colder temperatures and blustery days,” said Chris Fox, former Environmental Sciences professor at the University of Maryland. Fox has been studying weather for more than 20 years and spent last summer in the Durango area. Fox predicted five years ago that the “next big factor we’d be dealing with would be the wind after observing changes and “connecting the dots.”

the heat so far this June has been exceptional -- and, in some cases, record-breaking.

A strong upper-level high-pressure system, more reminiscent of midsummer than early June, has been responsible for the unusual spike in temperatures, which has extended from the Desert Southwest through the Southern Plains and into the deep South. The heat peaked in the Southwest on Sunday and Monday. The temperature soared to 110 degrees in Las Vegas on Sunday -- the earliest 110-degree reading on record -- and temperatures approached 120 degrees in Death Valley on both Sunday and Monday. The National Weather Service issued excessive-heat warnings and heat advisories for southern Nevada, the deserts of California and portions of Arizona, warning residents of the need to remain hydrated and limit outdoor activity.

In Las Vegas, the high temperature will be close to 105 degrees today and near 100 degrees on Wednesday, which will mark seven consecutive days with 100-plus temperatures.The unusually hot weather has been persistent in the Southern Plains, Missouri Valley and parts of the deep South so far in June as well. Temperatures have averaged five to eight degrees above normal across this region, including a 100-degree temperature in Dallas on Saturday, and heat advisories remain in effect in parts of Louisiana.

long-term monitoring has shown that animal communities living at great depth on the seafloor can change radically over remarkably short periods, and that these events are ultimately driven by climate. Such faunal changes are exemplified by the 'Amperima Event' – the sudden mass occurrence of the sea cucumber (holothurian) Amperima rosea recorded on the Porcupine Abyssal Plain (PAP) situated off the southwest coast of Ireland in the northeast Atlantic. Communities of animals living on the seabed there at depths of nearly 5000 metres have been monitored from 1989 to the present day. A major change occurred in the PAP community between 1996 and 1999 involving a number of animal groups, including sea anemones, segmented worms, sea spiders, sea squirts, brittle stars, and sea cucumbers, all of which increased in abundance. However, the population explosion in the sea cucumber Amperima rosea (hereafter Amperima) was particularly striking – thus the 'Amperima Event'. Before 1996 the sea cucumber was found in only ones or twos. They were very rare. But by 1999, the sea cucumber reached such high densities that if you were able to walk on the deep seafloor, you would have difficulty in avoiding squashing them flat. Dr David Billet and his colleagues showed that the increase abundance and dominance of Amperima occurred over a very wide area, greater than the size of the UK. Changes are also apparent in the abundance of other animals living in the seabed, including the single-celled creatures inhabiting the sediments. The whole deep-sea world had been turned on its head. "What this strongly suggested," says Dr Billett, "is that the 'Amperima Event' did not simply reflect localised, chance changes in the abundances of one or two species. Instead, changes in the whole deep-sea animal community were driven by environmental factors."

"Whether it is the quality or the quality of the organic matter, or both, that matter," says Dr Billett, "it appears that changes in the density of animals such as Amperima are related to phytoplankton productivity in the overlying surface waters, which is affected by climate change."

SIGHTINGS OF exotic snake pipefish, swarms of jellyfish and an “unprecedented” rise in sea surface temperatures indicate climate change is having a significant effect on Ireland’s marine ecosystems, according to a new report.Swarms of jellyfish, increased wave heights off the southwest coast and a greater variety of warm-water species in Irish waters have also been recorded by the authors of the report published today by the Marine Institute.

The authors noted that increases of sea surface temperature – at a rate of 0.6 degrees a decade – have been recorded since 1994. This is “unprecedented” in the past 150 years, the Marine Institute says.This temperature rise has been linked to an increase in microscopic plants and animals, along with species of jellyfish. The institute says increased numbers of most warm-water fish species have been observed in Irish waters.

Killer heat hits Korea, little relief this month

The temperature in South Jeolla hit highs of 34 degrees Celsius (93 degrees Fahrenheit) at the start of the month.

“We are considering announcing the number of heat fatalities on a weekly basis,” said an official at the Health Ministry, “to inform the public of the danger outside.”According to ministry records, 24 people rushed to emergency rooms on Aug. 2 and 3 had no other health problems. Another 16 who went to the hospital had conditions that were made worse by the heat.