Posted on November 22, 2013 by Bob Berwyn
NOAA’s winter outlook offers little relief for Arizona, New Mexico
By Bob Berwyn
FRISCO — Drought conditions may persist across the southwestern U.S. this winter and may redevelop across the Southeast, according to the seasonal outlook from NOAA’s Climate Prediction Center.
“Even though we don’t have La Niña, the atmosphere across the Pacific seems to be stuck in a La Niña mode … It’s been quite surprising to us, how persistent the pattern is,” said Mike Halpert, acting director of the Climate Prediction Center.
Parts of the Southwest, especially New Mexico, have been experiencing one of the driest periods on record, and Halpert said there is “decent agreement” in the CPC’s models on the climate signal that has resulted in the persistent trend. (more…)
Filed under: climate and weather, Drought, El Niño, La Niña | Tagged: climate, Climate Prediction Center, drought, El Nino, ENSO, La Niña, Southwest, winter weather outlook | 1 Comment »
Posted on November 12, 2013 by Bob Berwyn
Simultaneous changes in global precipitation patterns can’t be explained by natural variability
By Summit Voice
FRISCO — Scientists with Lawrence Livermore National Laboratory say unequivocally that greenhouse gases are affecting the distribution and intensity of precipitation around the world.
The new study, published Nov. 11 in the Proceedings of the National Academy of Sciences, shows how emissions of heat-trapping and ozone-depleting gases affect the distribution of precipitation through two mechanisms. Increasing temperatures are expected to make wet regions wetter and dry regions drier (thermodynamic changes); and changes in atmospheric circulation patterns will push storm tracks and subtropical dry zones toward the poles.
“Both these changes are occurring simultaneously in global precipitation and this behavior cannot be explained by natural variability alone,” said LLNL’s lead author Kate Marvel. “External influences such as the increase in greenhouse gases are responsible for the changes.” (more…)
Filed under: climate and weather, El Niño, extreme weather, global warming, La Niña | Tagged: climate change, Environment, global precipitation, global warming, greenhouse gases | 1 Comment »
Posted on November 1, 2013 by Bob Berwyn
‘We may have underestimated the efficiency of the oceans as a storehouse for heat and energy … ‘
The heat trapped by greenhouse gases isn’t missing — it’s in the ocean. bberwyn photo.
By Summit Voice
FRISCO — There’s more evidence that the world’s ocean are taking up the heat trapped by greenhouse gases at an increasing rate, according to a new study published in Science this week.
After reconstructing Pacific Ocean temperatures from the last 10,000 years, the researchers found that the middle depths have warmed 15 times faster in the last 60 years than they did during apparent natural warming cycles in the previous 10,000 years.
“We’re experimenting by putting all this heat in the ocean without quite knowing how it’s going to come back out and affect climate,” said study coauthor Braddock Linsley, a climate scientist at Columbia University’s Lamont-Doherty Earth Observatory. “It’s not so much the magnitude of the change, but the rate of change.” (more…)
Filed under: climate and weather, El Niño, Environment, global warming, La Niña | Tagged: global, greenhouse gases, Intergovernmental Panel on Climate Change, oceans, warming | Leave a Comment »
Posted on October 23, 2013 by Bob Berwyn
Warmer than average temperatures prevailed across much of the globe in September 2013. Graphic courtesy NCDC.
Southern hemisphere land-surface temps record warm for the month
By Summit Voice
FRISCO — For all the tweeting, squawking and general clamor from global warming deniers, you’d think the Earth was on the brink of a new ice age, but the facts show otherwise.
Once again during September, the average global temperature was near record highs, at 1.15 degrees above the 20th century average — tied with 2003 as the fourth-warmest on record.
Even without the warming effect of El Niño, the average global ocean temperature was .97 degrees above the 20th century average, tying with 2006 as the fourth-warmest on record. For the year, land and sea surface temperatures together are on pace to register as the sixth warmest on record, according to the National Climatic Data Center, which released its monthly climate update a few days late due to the shutdown. (more…)
Filed under: climate and weather, El Niño, global warming, La Niña, seasons | Tagged: Australia heatwave, climate, global temperature records, global warming, National Climatic Data Center, Southern hemisphere record warmth | Leave a Comment »
Posted on October 18, 2013 by Bob Berwyn
Cooler Pacific Ocean temps may drive tornado activity into southern U.S.
A tornado near Lakeview, Texas. Photo courtesy NOAA.
By Summit Voice
FRISCO — After studying more than 56,000 tornados, researchers at the University of Missouri say they’ve found a clear link between Pacific Ocean sea surface temperatures and the patterns of storms that spawn the violent twisters. The findings could help scientists predict the type and location of tornado activity in the U.S.
When surface sea temperatures were warmer than average, the U.S. experienced 20.3 percent more tornadoes that were rated EF-2 to EF-5 on the Enhanced Fuijta (EF) scale. (The EF scale rates the strength of tornados based on the damage they cause. The scale has six category rankings from zero to five.)
“Differences in sea temperatures influence the route of the jet stream as it passes over the Pacific and, eventually, to the United States,” said Laurel McCoy, an atmospheric science graduate student at the MU School of Natural Resources. “Tornado-producing storms usually are triggered by, and will follow, the jet stream. This helps explain why we found a rise in the number of tornadoes and a change in their location when sea temperatures fluctuated.” (more…)
Filed under: climate and weather, Environment, La Niña | Tagged: climate, extreme weather, National Oceanic and Atmospheric Administration, Pacific Decadal Oscillation, Sea surface temperature, tornadoes | Leave a Comment »
Posted on August 24, 2013 by Bob Berwyn
Fall and winter outlook still murky
Seasonal weather forecasters look out to sea surface temperatures in the equatorial Pacific to get an idea of what weather patterns may bring.
Without a stron El Niño or La Niña in the outlook, forecasters are not confident of projecting pronounced temperature or precipitation anomalies.
By Bob Berwyn
FRISCO — With no strong El Niño or La Niña on the horizon, forecasters are struggling even more than usual to develop seasonal outlooks for the western U.S. The periodic El Niño-La Niña cycle is a large-scale shift in the Pacific involving a complex interplay of winds, ocean currents and sea surface temperatures.
In the U.S. the warm El Niño phase is associated with wetter than average conditions in the Desert Southwest and California, and can result in below average precipitation in the Pacific Northwest.
La Niña, on the other hand, has been linked with Southwestern drought conditions and heavy precipitation in the Pacific Northwest. That persistent moist flow off the northwestern Pacific can also favor parts of Colorado with good winter snows, but the ENSO climate signal is more marginal in Colorado than in other areas. (more…)
Filed under: climate and weather, Colorado, Drought, El Niño, La Niña, seasons, Snow and weather, Summit County snow and weather | Tagged: climate, Colorado winter snow, El Nino, ENSO, La Niña, seasonal forecast, weather | Leave a Comment »
Posted on August 10, 2013 by Bob Berwyn
Hurricane Sandy as seen from NOAA’s GOES-13 satellite on October 28, 2012. Photo courtesy NOAA/NASA.
Warm ocean temps, strong West Africa rainy season boost chances for tropical formation
By Summit Voice
FRISCO — Federal weather experts this week reaffirmed their earlier projections of an active hurricane season in the Atlantic, with hemispheric patterns similar to those that have produced many active Atlantic hurricane seasons since 1995.
Ingredients for tropical storm formation include above-average Atlantic sea surface temperatures and a stronger rainy season in West Africa, which produces wind patterns that help turn storm systems there into tropical storms and hurricanes.
The peak of the Atlantic hurricane season is just ahead, from mid-August through mid-October. (more…)
Filed under: climate and weather, La Niña, seasons, tropical storms and hurricanes | Tagged: 2013 Atlantic hurricane season, hurricanes, National Hurricane Center, Tropical cyclone, weather | Leave a Comment »
Posted on August 7, 2013 by Bob Berwyn
Strongest climate signals coming from Arctic and extreme weather events
Many parts of the globe reported record and near-record temps in June 2013.
By Bob Berwyn
FRISCO — Some of the most compelling signs of global warming impacts continued to come from the Arctic in 2012, where sea ice extent reached a record low and Greenland experienced record surface melting last summer.
Another worrying sign is the warming in permafrost regions, where significant thawing could release a new surge of heat-trapping greenhouse gases that would intensify warming.
The average global temperature for the year was among the top-10 warmest on record, and other climate observations also are consistent with what to expect in a warming world, according to climate experts who released the 2012 State of the Climate report this week. (more…)
Filed under: Arctic, climate and weather, El Niño, Environment, global warming, La Niña | Tagged: 2012 state of the climate report, American Meteorological Society, climate change, global warming, National Climatic Data Center | 1 Comment »
Posted on July 19, 2013 by Bob Berwyn
Many northern hemisphere land areas reported near-record warmth
Most areas of the globe reported temperatures running well above the 20th century average during June 2013.
By Summit Voice
FRISCO — The Globally averaged land and sea surface temperature was 1.15 degrees above the 20th century average, tying with 2006 as the fifth-warmest on record, according to the National Climatic Data Center monthly summary report released this week.
The average land-surface temperature was even warmer. At 1.89 degrees above average, it was the third-warmest June on record over the world’s land areas. Record-setting warmth was reported from many locations in northern Canada, far northwestern Russia, southern Japan, the Philippines, part of southwestern China, and central southern Africa.
The year to-date is also running hot, tied with 2003 as the seventh-warmest January to June period on record, with a combined global land and ocean average surface temperature that was 1.06 degrees above the 20th century average. (more…)
Filed under: climate and weather, El Niño, Environment, global warming, La Niña | Tagged: climate change, global climate, global warming, Instrumental temperature record, June 2013 global temperatures, National Oceanic and Atmospheric Administration, Sea surface temperature | Leave a Comment »
Posted on July 15, 2013 by Bob Berwyn
Early warning could help regional preparedness efforts
A new climate model could help project El Niño conditions a year in advance.
By Summit Voice
FRISCO — Forecasting the emergence of El Niño well in advance has long been a goal of climate scientists and a team of German researchers say they may have devised a model that extends the lead time to a year.
Published recently in the Proceedings of the National Academy of Sciences, their paper describes how the model uses high-quality data of air temperatures as the basis for making long-term projections about El Niño, a warm phase of a periodic Pacific Ocean cycle that affects climate and weather around the world.
“Enhancing the preparedness of people in the affected regions by providing more early-warning time is key to avoiding some of the worst effects of El Niño,” said Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research, who co-authored the paper with Josef Ludescher, of Justus-Liebig Universität Giessen. (more…)
Filed under: climate and weather, El Niño, La Niña | Tagged: climate, climate projections, El Nino, ENSO, Hans Joachim Schellnhuber, Potsdam Institute for Climate Impact Research | Leave a Comment »