The old Stapleton International Airport site and Denver International Airport are separated by 12 miles. Is it accurate to compare weather between the two locations?
These announcements are common and we all take notice when we hear them and they make for great water cooler chat topics but are these claims accurate?
In 1995 Denver finally opened its new airport, Denver International Airport, out on the plains east of the city. This new facility, 12 miles as the crow flies northeast of the old Stapleton International Airport, moved the airport from an urban environment to a rural one and more than 19 miles from the center of Denver. Following that move, the National Weather Service (NWS) began taking some of its official measurements at the glistening new airport. In doing so, some say Denver’s climate records have forever been altered and as such any weather record should have an asterisk attached to it.
Denver and Thornton's March 2009 climatological preview
March in Denver typically means frequent and rapid weather changes. The days grow longer and we start enjoying more sunshine and sometimes summer-like weather. However, on occasion arctic air masses can still force their way south into Colorado dropping temperatures quickly and markedly.
These changes are due to Marches “in between” status – elements during the month have much in common with winter and spring. In addition to arctic fronts, Pacific storms frequently move across Colorado from the west and warm moist air streams up from the Gulf of Mexico northeastward into the state. When these cold fronts collide with the warmer air masses the result can be some crazy weather.
A pretty interesting headline isn’t that? I admit that is probably a bit more sensationalistic than what is really called for. However, that would seem to be one of the conclusions from the author and analyst of a recent survey.
3,146 earth scientists from various areas of expertise were surveyed for their opinions and in many ways, the data was not surprising. Two questions were key to the study:
Have mean global temperatures risen compared to pre-1800s levels?
Has human activity been a significant factor in changing mean global temperatures?
Extremely high clouds, known as deep convective clouds, are typically associated with severe storms and rainfall. In this AIRS image of Hurricane Katrina, taken August 28, 2005, the day before Katrina made landfall in Louisiana, the eye of the storm was surrounded by a "super cluster" of 528 deep convective clouds (depicted in dark blue). The temperatures of the tops of such clouds are colder than 210 degrees Kelvin (-82 degrees Fahrenheit). Image credit: NASA/JPL
Scientists are NASA’s Jet Propulsion Laboratory in Pasadena, CA recently released the results of a study that determined that global warming is causing an increase in high clouds and a corresponding increase in severe storms and rainfall. This is not unlike previous warnings issued by some scientists, in particular those warnings of an increase in hurricane intensity and frequency in the Atlantic. Thus far those previous warnings have not bore out. Will this one?
PASADENA, Calif. — The frequency of extremely high clouds in Earth’s tropics — the type associated with severe storms and rainfall — is increasing as a result of global warming, according to a study by scientists at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
In a presentation today to the fall meeting of the American Geophysical Union in San Francisco, JPL Senior Research Scientist Hartmut Aumann outlined the results of a study based on five years of data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua spacecraft. The AIRS data were used to observe certain types of tropical clouds linked with severe storms, torrential rain and hail. The instrument typically detects about 6,000 of these clouds each day. Aumann and his team found a strong correlation between the frequency of these clouds and seasonal variations in the average sea surface temperature of the tropical oceans.
For every degree Centigrade (1.8 degrees Fahrenheit) increase in average ocean surface temperature, the team observed a 45-percent increase in the frequency of the very high clouds. At the present rate of global warming of 0.13 degrees Celsius (0.23 degrees Fahrenheit) per decade, the team inferred the frequency of these storms can be expected to increase by six percent per decade.
Climate modelers have long speculated that the frequency and intensity of severe storms may or may not increase with global warming. Aumann said results of the study will help improve their models.
“Clouds and rain have been the weakest link in climate prediction,” said Aumann. “The interaction between the daytime warming of the sea surface under clear-sky conditions and increases in the formation of low clouds, high clouds and, ultimately, rain is very complicated. The high clouds in our observations—typically at altitudes of 20 kilometers (12 miles) and higher—present the greatest difficulties for current climate models, which aren’t able to resolve cloud structures smaller than about 250 kilometers (155 miles) in size.”
Aumann said the results of his study, published recently in Geophysical Research Letters, are consistent with another NASA-funded study by Frank Wentz and colleagues in 2005. That study found an increase in the global rain rate of 1.5 percent per decade over 18 years, a value that is about five times higher than the value estimated by climate models that were used in the 2007 report of the Intergovernmental Panel on Climate Change.
JPL manages the AIRS project for NASA’s Science Mission Directorate, Washington. For more information on AIRS, visit http://airs.jpl.nasa.gov/ .
As we continue on what has been a relatively dry season thus far, cold and dry are the key words to remember when it comes to January. The month is the coldest of the year and the second driest as well. Just how cold can January get? The record low temperature for each day of the month is at least 10 degrees below zero.
What are the odds of a white Denver Christmas? Not very good.
As Christmas gets closer everyone always wonders if we are going to get the proverbial white Christmas. Unfortunately, if you look at Denver and Thornton weather history, the chances arent all that good but it also depends on what you define as a white Christmas. December just isnt that snowy of a month, ranking as only the fourth snowiest (behind March, November and April) so historically we have a bit of a disadvantage.
These extraordinary satellites will provide everything from lightning mapping and improved hurricane forecasting to monitoring of sea surface temperatures. The press release from NOAA provides some of the details on this exciting endeavor:
NOAA, NASA Select Contractor to Build GOES-R Series Spacecraft
New Geostationary Satellites Will Give Forecasters Better Information
December 2, 2008
NOAA and NASA officials announced today Lockheed Martin Space Systems Company, of Denver, Colo., has been selected to build two spacecraft for NOAA’s next generation geostationary satellite series, GOES-R. There are two options, each providing for one additional satellite. Scheduled for launch in 2015, the new satellites will provide more data in greater detail which is essential to creating accurate weather forecasts.
The contract has a total value of $1.09 billion for the two satellites. A separate contract to build the GOES-R ground system, which receives, processes and distributes data transmitted from the spacecraft, will be announced later in 2009, officials said.
“GOES-R, with its highly advanced instruments and sensors, will provide about 50 times more weather and climate data than is available with NOAA’s current fleet of geostationary satellites,” said Mary Kicza, assistant administrator for NOAA Satellite and Information Service. “The American public will see real life-saving benefits from this satellite system with more timely forecasts and warnings for severe weather.”
GOES-R will improve the monitoring of sea surface temperatures and also provide more data to hurricane forecasters by giving sharper images of storms every 30 seconds, instead of every 7.5 minutes as the current satellites provide.
Additionally, GOES-R will carry a first-of-its-kind instrument called the Geostationary Lightning Mapper, which will quickly locate all lightning flashes occurring anytime, anywhere in the Western Hemisphere. The lightning mapper will aid in predicting tornadoes, which often spawn from lightning-packed thunderstorms.
Other key benefits expected from GOES-R include: greater monitoring of surface temperatures in metropolitan areas to improve warnings for heat stress, and better data to bolster the forecasts for unhealthy air quality days. GOES-R will feature advanced solar monitoring instruments for space weather forecasts and warnings of solar storms. These storms endanger billions of dollars worth of commercial and government assets in space and cause power surges for the satellite-based electronics and communications industry.
George Morrow, director of Flight Project for NASA’s Goddard Space Flight Center in Greenbelt, Md. said, “NASA Goddard is excited to be NOAA’s partner in this next generation GOES development and we look forward to delivering an outstanding observatory for their operational use.”
NOAA funds, manages and will operate the GOES-R program. NASA’s Goddard Space Flight Center oversees the acquisition of the GOES-R spacecraft and instruments for NOAA.
This image shows the tracks of hurricanes that occurred during the 2008 season. Click for larger image.
Sunday, November 30th marks the close of the hurricane season and the National Oceanic and Atmospheric Administration says it was one for the record books. The season marks one of the more active in the last 64 years overall and resulted in a record number of consecutive storms striking the United States.
According to Gerry Bell, Ph.D, the lead seasonal forecaster at NOAA, “This year’s hurricane season continues the current active hurricane era and is the tenth season to produce above-normal activity in the past 14 years.” It is important to note however that comprehensive record keeping of hurricanes has only been occurring for the last 64 years so there is not a great deal of data to draw upon.
In all, a total of 16 named storms formed this season, eight of which were hurricanes. Five of those were major hurricanes of category 3 strength or higher. An average hurricane season has 11 named storms, six hurricanes and two major hurricanes. In May at the start of the 2008 season, NOAA forecasters predicted 12 to 16 named storms and then in August upped their predictions to 14 to 18 named storms. This represents the first time in recent years forecasters had accurately bracketed the number of storms. In 2007 NOAA predicted 10 hurricanes and only six formed. The year prior, 2006, nine hurricanes were forecasted by NOAA but only five formed. In 2005, the year Hurricane Katrina devastated New Orleans in the worst U.S. natural disaster, the forecasts underestimated storm activity.
2008 ties as the fourth most active season in terms of named storms (16) and major hurricanes (5). It also tied as fifth most active in terms of hurricanes overall (8) since 1944.
From NOAA, most notably:
For the first time on record, six consecutive tropical cyclones (Dolly, Edouard, Fay, Gustav, Hanna and Ike) made landfall on the U.S. mainland and a record three major hurricanes (Gustav, Ike and Paloma) struck Cuba. This is also the first Atlantic season to have a major hurricane (Category 3) form in five consecutive months (July: Bertha, August: Gustav, September: Ike, October: Omar, November: Paloma).
Bell attributes the active season to ongoing increased activity since 1995, lingering La Nina effects and warmer tropical Atlantic Ocean effects.
Here is a fascinating video from NOAA using satellite imagery of the entire hurricane season:
December weather preview - what can we expect in Denver?
December brings with it the official start to winter and at the same time we find ourselves hoping we get moisture in the near future. As of this writing, the mountain snowpack in all basins are well below normal, with some as low as 27% of normal. Here in town our our annual snowfall is well below normal as well. In Colorado the snow season starts on July 1st and between that date and November 30th, Denver averages 16.9 inches of snow. Thus far, ThorntonWeather.com has measured a meager 0.2 inch and the official total for Denver taken at the site of the old Stapleton International Aiport stands at 0.8 inch!
Now that is heavy metal! The TIV 2 is a machine designed specifically for driving into a tornado. Image courtesy Discovery Channel.
The 2008 tornado season was historical for its ferocity. Record breaking numbers of twisters struck Tornado Alley with a frequency not seen in years. In June, north central and western Kansas were ground zero for tornado outbreaks that went on for days.
ThorntonWeather.com continues to be granted special access to the Discovery Channel’s Storm Chasers (Sunday’s @ 8:00pm MST) footage. In this coming Sunday’s episode, the crew finds itself right in the thick of things. The episode guide says:
No Place Like Kansas – Nov. 23 at 10 p.m. ET/PT
With the DOW and all the chase vehicles up and running again, the team finds themselves hunting in the same territory as the rival TVN crew. Tornadoes are forming all over western Kansas on what looks like the biggest day of the season.
This week’s sneak peak – A funnel cloud begins to form in the skies over Quinter, Kansas as the the Storm Chasers scramble to approach it.
Weather, natural disasters & climate news and information.
