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Tout ce qui a été posté par iceberg

  1. The National Snow and Ice Data Center has just released their latest update (month of May) on the sea ice situation up in the Arctic. Here are some of the main highlights from their report..... Arctic sea-ice situation --Sea ice extent is below the long-term average. --Sea ice extent is very close to the low levels seen in May 2007. (May 2008 extent was 0.11 million sq. miles greater than May 2007). --Spring ice cover is thin. --The average decline rate this May was 3000 sq. miles per day faster than May 2007. --The average Arctic Ocean surface air temperatures in May were 1 to 3 degrees celsius (2 to 5 degrees F) above normal. --Thin ice that covers the Arctic Ocean is showing signs of early breakup. --There is a distinct lack of thick, resilient multi-year ice, but the thin ice is farther north than normal, which may make it less vunerable than if it was in its normal position.
  2. PRECIP FORCAST FOR SUMMER 2008 (BRETT ACCUWEATHER ) The second map below shows what I expect for summer precipitation. Keep in mind summer precipitation can vary greatly over short distances due to the convective (showers/t-storms) nature of precipitation. The neon green color indicates above-normal rainfall, the base green color indicates near-normal, while the yellow/brown color shows where I expect the summer to be drier than normal.
  3. 2008 SUMMER FORCAST ( BRETT FROM ACCUWEATHER ) After sorting through global land and ocean data, long range models and past climate I have finally come up with a summer 2008 forecast for Canada. Some of the more key things that I have considered....... --A fading La Nina --A cool phase of the PDO (Pacific Decadal Oscillation) --Much of the North Atlantic having above-normal sea-surface temperatures. --Cooler-than- normal Pacific waters from the Gulf of Alaska to the U.S. West coast and off of Baja (part of the cool phase PDO) --Drier-than-normal ground southern prairies. --I expect a more active Atlantic tropical storm/hurricane season with a greater than normal threat to Atlantic Canada, especially in late- August and September. --The mean position of the U.S. high Plains ridge of high pressure will allow a greater than normal amount of thunderstorm complexes to track from the central Plains to the Great Lakes as they run along the "rim of the ridge" The top map shows my prediction for temperatures across Canada for the summer as a whole. The red areas are above normal, green near normal and blue is below normal.
  4. METEO MARS SOL 1 meteo mars pour le 27 Mai 2008. Skies were clear and sunny on Sol 1 on Mars. The temperature varied between minus 80 degrees in the early morning and minus 30 C degrees in the afternoon. The average pressure was 8.55 millibars, which is less than a 1/100th of the sea level pressure on Earth. The weather station was activated in the first hour after landing on Mars. Measurements are being recorded continuously. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver. The Canadian Space Agency contributed Phoenix's meteorological station. The University of Aarhus in Denmark contributed the telltale on the meteorology mast. Image Canadian Space Agency/University of Aarhus
  5. noaa 34 note the low fog in the back ground.....
  6. Is This The Last Barrier to a Climate Collapse? Dr. Tim Flannery, an Australian global warming activist, mammalogist and palaeontologist has proposed a radical solution to slow down global warming, which in his words is the last barrier to a climate collapse, according to The Age. Flannery say's climate change is happening so quickly that mankind may need to pump sulphur into the upper atmosphere in order to survive. His technique places sulphur gas into the earth's stratosphere to block out more of the sun's rays. How would this be done? Sulphur would be added to jet fuel and dispersed in the stratosphere. When should this happen? Flannery says we may need to be doing this in five years time. This process would also cause the sky to change color. But what color? Yellow? According to Flannery, the world was much more susceptible to greenhouse gas emissions that had been thought eight years ago. "Regardless of what happened to emissions in the future, there was already far too much greenhouse gas in the atmosphere," he said. "Cutting emissions was not enough. Mankind now has to take greenhouse gases out of the air," he added. In particular, carbon should be taken out of the air and converted into charcoal, then plowed into farmers' fields. Flannery was named Australian of the year for 2007. AP
  7. la neige a 16c a lynn lake !!! 16 May 2008 22:00 Mostly Cloudy 8 68 2 N 22 gust 39 100.9 15 21:00 Mainly Sunny 12 41 -1 NW 17 100.8 15 20:00 Mainly Sunny 14 36 -1 NW 30 gust 41 100.8 15 19:00 Mainly Sunny 14 35 -1 NW 24 gust 46 100.8 15 18:00 Light Snow 16 28 -2 NW 42 gust 59 100.7 15 17:00 Light Snow 16 29 -2 NW 45 gust 63 100.6 15 16:00 Sunny 16 33 0 NW 41 gust 50 100.6 15 15:00 Sunny 16 37 1 NW 42 gust 52 100.6 15 14:00 Sunny 16 38 1 NNW 35 100.6 15 13:00 Light Drizzle 14 42 1 WNW 35 gust 50 100.7 15 12:00 Sunny 14 44 2 NW 32 100.6 15 11:00 Sunny 13 48 2 NW 26 gust 37 100.6 15 10:00 Sunny 12 51 2 NW 28 gust 39 100.6 15 9:00 Sunny 10 61 3 NW 32 100.6 15 8:00 Sunny 8 72 3 NW 30 100.5 15 7:00 Sunny 7 80 3 NW 28 100.5 15 6:00 Sunny 6 83 3 NW 21 100.4 15 5:00 Clear 6 86 4 NW 18 100.3 15 4:00 Clear 6 89 4 WNW 18 100.3 15 3:00 Clear 6 88 4 W 15 100.3 15 2:00 Clear 6 90 4 SW 13 100.3 15 1:00 Rain 7 86 5 N 11 gust 50 100.5 5 00:00 Rain 9 72 4 SW 15 100.5 link : http://www.weatheroffice.gc.ca/trends_tabl...l_metric_e.html
  8. Updated Summer Monthly Forecast The newly updated European model monthly forecast for North America was just released yesterday. The most glaring thing I see from the forecast is the reflection of the cooler phase of the PDO (Pacific Decadal Oscillation). The model is now clearly seeing this and is forecasting below normal temperatures right along and just off the West Coast of North America from Alaska to southern California through a good part of the summer. The model also continues to forecast some upper atmospheric blocking (ridge of high pressure) between Labrador and Greenland through July, similar to what we are seeing currently in May. The blocking then backs off to the northeast (eastern Greenland) by August. Here is how I interpret what the model is forecasting in terms of the mean pattern during a particular month...... June The model predicts a weak upper-level high (ridge) near the Aleutians and just north of Labrador. There also appears to be a positive phase of the Arctic Oscillation. Possible impacts..... --Very warm compared to normal over the Intermountain region of the western U.S. --Cooler and slightly wetter than normal in British Columbia down through Washington and Oregon. --Above-normal temperatures in northern Canada, but cooler in the Arctic region. --Slightly cooler than normal for eastern Canada and the Maritimes. --Above-normal temperatures and drier than normal conditions for the western prairies. --More thunderstorms compared to normal over Manitoba and northwestern Ontario. --Wetter pattern over the Northeastern U.S. July The model predicts fairly similar upper-level conditions as those for June. --Drier than normal over the Southwestern U.S. --Cooler and slightly wetter than normal from the Pacific Northwest coastal region then up into western BC. --Hot across the interior West of the U.S. and southwestern prairies. --Near to slightly cooler than normal temperatures from the Midwestern U.S> through the Northeast and into Eastern Canada and the southern Maritimes. More widespread showers and thunderstorms compared to normal from the Midwestern U.S. through the Northeast and into eastern Canada. --Not a hot month for the Southeast U.S accord ing to the model., but I fear the lack of moisture in the ground could actually make it hotter than normal due to a reduction of evaporative cooling. August --The immediate West Coast remains cooler than normal from Oregon through BC. --A hot month relative to normal from the U.S. Rockies into the central Plains, including the southwestern Prairie region of Canada. --Temperatures for much of the eastern U.S. and eastern Canada are near normal. --Greater than normal rainfall along the Gulf coast. --More widespread showers and thunderstorms compared to normal over Ontario, the Great Lakes and interior Northeast. --More humid with possible tropical rainstorm influences over the coastal Maritimes and Newfoundland the second half of the month. Accuweather....... Brett Anderson
  9. By RANDOLPH E. SCHMID, AP Science Writer WASHINGTON - The El Nino phenomenon that has puzzled climate scientists in recent decades may have assisted the first trip around the world nearly 500 years ago. Explorer Ferdinand Magellan encountered fair weather on Nov. 28, 1520, after days of battle through the rough waters south of South America. From there his passage across the Pacific Ocean may have been eased by the calming effects of El Nino, researchers speculate in a new study. When an El Nino occurs, the waters of the Equatorial Pacific become warmer than normal, creating rising air that changes wind and weather patterns. The effects can be worldwide, including drought in the western Pacific and more rain in Peru and the west coast of South America. Tree ring data indicate that an El Nino was occurring in 1519 and 1520 and may even have begun in 1518. After passing through the strait later named for him, Magellan sailed north along the South American coast and then turned northwest, crossing the equator and eventually arriving at the Philippines, where he was killed in a battle with natives. Magellan was seeking the so-called spice islands, now part of Indonesia, and his course took him north of that goal. But the route may have been dictated by mild conditions and favorable winds during an El Nino, anthropologists Scott M. Fitzpatrick of North Carolina State University and Richard Callaghan of the University of Calgary, Canada, propose in a new study of his trip. Their research is summarized in Friday's edition of the journal Science and is scheduled to be published in full in the August edition of the Journal of Pacific History. They were studying early exploration trips and were struck by the fact that Magellan sailed unusually far north, Fitzpatrick explained in a telephone interview. "We had not considered El Nino until afterward, when we were trying to account for why the winds were so calm when he came into the Pacific," he said. "We knew it was unusual." The researchers used a computer to model wind and weather conditions across the Pacific during an El Nino and then compared that to Magellan's route. Magellan's journals show that many of the crew had died or were sick with scurvey, so he may simply have chosen to sail with the existing winds and currents, reducing the number of crew needed to operate his ships, Fitzgerald said. "It could have been an adept maneuver," the researchers wrote, allowing him to move west along the past of least resistance. In his writings, Magellan said he chose the northerly route because of reports of a famine in the spice islands. This also could be accurate, Callaghan and Fitzpatrick say, as El Nino conditions often result in drought in that region. Magellan had received correspondence from a friend in the spice islands before setting out and so may have known about a famine there, Fitzgerald said. But that cannot be determined for certain, because the correspondence was destroyed in the great Lisbon earthquake of 1755. While the actual reasons for Magellan's choice of route remain uncertain, El Nino conditions "may have been largely responsible for structuring the route and extent of what many consider the world's greatest voyage," the researchers wrote. The trip, in fact, may be the earliest record of an El Nino, Fitzpatrick said. Sir Francis Drake encountered mild conditions in the Strait of Magellan when he sailed through in 1578, but he then faced months of Pacific storms that scattered his ships, sinking one. Captain James Cook seems also to have benefited from El Nino conditions centered on 1769 during his Pacific exploration.
  10. LE 17 MAI 2008. LINK: : http://www.aad.gov.au/weather/aws/dome-a/index.html
  11. Climate Models Overheat Antarctica, New Study Finds (May 8, 2008) Computer analyses of global climate have consistently overstated warming in Antarctica, concludes new research by scientists at the National Center for Atmospheric Research (NCAR) and Ohio State University. The study can help scientists improve computer models and determine if Earth's southernmost continent will warm significantly this century, a major research question because of Antarctica's potential impact on global sea-level rise. "We can now compare computer simulations with observations of actual climate trends in Antarctica," says NCAR scientist Andrew Monaghan, the lead author of the study. "This is showing us that, over the past century, most of Antarctica has not undergone the fairly dramatic warming that has affected the rest of the globe. The challenges of studying climate in this remote environment make it difficult to say what the future holds for Antarctica's climate." The study marks the first time that scientists have been able to compare records of the past 50 to 100 years of Antarctic climate with simulations run on computer models. Researchers have used atmospheric observations to confirm that computer models are accurately simulating climate for the other six continents. The models, which are mathematical representations of Earth's climate system, are a primary method for scientists to project future climate. Antarctica's climate is of worldwide interest, in part because of the enormous water locked up in its ice sheets. If those vast ice sheets were to begin to melt, sea level could rise across the globe and inundate low-lying coastal areas. Yet, whereas climate models accurately simulate the last century of warming for the rest of the world, they have unique challenges simulating Antarctic climate because of limited information about the continent's harsh weather patterns. The study was published on April 5 in Geophysical Research Letters. It was funded by the National Science Foundation, NCAR's primary sponsor, and the Department of Energy. The authors compared recently constructed temperature data sets from Antarctica, based on data from ice cores and ground weather stations, to 20th century simulations from computer models used by scientists to simulate global climate. While the observed Antarctic temperatures rose by about 0.4 degrees Fahrenheit (0.2 degrees Celsius) over the past century, the climate models simulated increases in Antarctic temperatures during the same period of 1.4 degrees F (0.75 degrees C). The error appeared to be caused by models overestimating the amount of water vapor in the Antarctic atmosphere, the new study concludes. The reason may have to do with the cold Antarctic atmosphere handling moisture differently than the atmosphere over warmer regions. A chilling ozone hole Part of the reason that Antarctica has barely warmed has to do with the ozone hole over the continent. The lack of ozone is chilling the middle and upper atmosphere, altering wind patterns in a way that keeps comparatively warm air from reaching the surface. Unlike the rest of the continent, the Antarctic Peninsula has warmed by several degrees, in part because the winds there are drawing in warmer air from the north. The models generally capture these wind changes, although sometimes incompletely. The study delivered a mixed verdict on Antarctica's potential impact on sea-level rise. The Intergovernmental Panel on Climate Change, which operates under the auspices of the United Nations, has estimated that sea-level rise could amount to 7 to 23 inches (18-59 centimeters) this century, in part because of melting glaciers worldwide. The Geophysical Research Letters paper suggests that warming in Antarctica over the next century could offset that by about 2 inches if the continent warms by 5.4 degrees F (3 degrees C), as computer models have indicated. The reason is that the warmer air over Antarctica would hold more moisture and generate more snowfall, thereby locking up additional water in the continent's ice sheets. But the authors caution that model projections of future Antarctic climate may be unreliable. "The research clearly shows that you can actually slow down sea-level rise when you increase temperatures over Antarctica because snowfall increases, but warmer temperatures also have the potential to speed up sea-level rise due to enhanced melting along the edges of Antarctica," says Monaghan, who did some of his research at Ohio State University before coming to NCAR. "Over the next century, whether the ice sheet grows from increased snowfall or shrinks due to more melt will depend on how much temperatures increase in Antarctica, and potentially on erosion at the ice sheet edge by the warmer ocean and rising sea level." "The current generation of climate models has improved over previous generations, but still leaves Antarctic surface temperature projections for the 21st century with a high degree of uncertainty," adds co-author and NCAR scientist David Schneider. "On a positive note, this study points out that water vapor appears to be the key cause of the problematic Antarctic temperature trends in the models, which will guide scientists as they work to improve the climate simulations." The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under primary sponsorship by the National Science Foundation (NSF). Opinions, findings, conclusions, or recommendations expressed in this document are those of the author(s) and do not necessarily reflect the views of the National Science Foundation, NASA, or other funding agencies. UPI
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