Updated: August 1, 2012:
Over the years, I have received quite a few questions about why the Denver weather observations are taken at DIA, and does it make a big difference. The basic answer is that we need to have the weather observations for aviation safety, so they are taken at the airport.
No One Lives at the airport!
Changing the location from Stapleton to DIA has made a difference in the temperature and precipitation reports for Denver. Prior to the move from Stapleton to DIA, the National Weather Service did extensive comparisons of the data from both sites and found that the actual numbers were reasonably close, but it seems that DIA does trend a couple of degree warmer in the summer, but colder in the fall and winter.This is partly due to the fact that during the summer the afternoon clouds and thunderstorms usually build over the mountains and move east. Downtown Denver gets in the shade of those clouds before they reach DIA.It appears that the weather station at City Park is warmer than DIA most of the time. In fact, so far in 2012, it has been warmer at City Park, compared to DIA in 6 out of 7 months. July was a half a degrees warmer at DIA, with an average temperature of 78.9 degrees. Both DIA and City Park established new records for the hottest month ever in Denver - beating 77.8° in 1934.In fact, the new weather station is running nearly 2 degrees warmer so far in 2012 than the weather station at DIA. Seven months into the year, the new weather station is on track to make 2012 the hottest year on record for Denver. The average temperature for the year so far at City Park is 56.23 degrees. DIA is reporting 54.44 degrees since January 1st. In 1934, the current "hottest year on record", the average temperature was 54.8 degrees. Of course, we still have 5 months to go, so I will keep you updated!There are times in the cooler seasons when the location makes a big difference, for example when a "back door" cold front hits DIA with wind, cold and snow hours before it gets to downtown Denver. Most of the time, however, the weather from one locale to the next is not as much as you might expect.Despite the fact that the data is pretty close, we are frequently asked about why the temperatures are not given for the downtown area. In response, local TV stations have placed weather instruments at their studios, but these are not official observations and do not go into the climate records for the city.
A New Weather Station!
It has long been desirable to develop a much more accurate weather station and have it sanctioned by the National Weather Service as the official downtown Denver observation. The addition of another set of hourly observations would put an accurate report right in the middle of the surrounding reports from the outlying airports.
The Denver area has been lacking a set of highly accurate downtown observations since the closing of Stapleton Airport and the move nearly 20 miles northeast to DIA. Since that time, the observation network for the fast growing Denver area has consisted of a ring of reports from the suburbs, but little reliable data from the city. Hourly observations are available from Buckley AFB (KBKF), Centennial Airport (KAPA), Denver International Airport (KDEN) and from Boulder-Jeffco Airport (KBJC).None of these sites are within 12 miles of downtown and in the case of DIA (the official observation), the site is 18 miles away from the center of the city. As the subject of climate change continues to increase in importance, it is important to get additional high quality observations in the Denver area.
History Of Denver Weather Stations
The Stapleton site was used starting in the 1920s, when the airport was established there. Prior to Stapleton, the Denver observations were taken from the Denver Water Board, the Post Office and other downtown locations since the early 1870s. The actual reporting station location has been moved 4 or 5 times over the years, for a variety of reasons. Obviously, as scientists, we would love to have nearly 140 years of rock solid consistent data, but we do the best we can with the changing locations.I always have said, "talk to your congressman, not your weatherman" - as the issue is much more fiscal science and not physical science - we are talking tax dollars! The problem with adding a new weather station has been threefold - 1) Funding - using tax dollars. 2) Finding a suitable location - difficult to find an open area in the city. 3) Getting permission from a variety of different government agencies.
How To Get A High End Weather StationUnlike a home or hobby type weather station, official observation sites are expensive, requiring high end, extremely accurate equipment, set in a location that meets the stringent requirements of the National Weather Service. The combination of cost and finding a proper site in a crowded urban area seemed to make such a new weather station an unlikely prospect.But we found a way to fund a high end weather station! Vaisala, a leading manufacturer of extremely accurate weather instruments, stepped up to the plate. Based in Helsinki, Finland, Vaisala is the maker of radiosonde equipment the small instrument package that is sent up with weather balloons. Vaisala has a national office located in Broomfield and provided the funding and equpiment for a high end weather station at City Park near the Denver Museum of Nature and Science.A unique synergy between Vaisala, the National Weather Service and the City of Denver enabled us to develop a new weather station in the metro area at little cost, but great benefit to taxpayers!This weather station is operational and the observations are now available from the National Weather Service and from the Denver Museum of Nature and Science. These weather observations will not replace those from DIA, but will augment the overall climate data record for the Denver Metro Area.
Here is a link to check the National Weather Service summary, including the new weather station.Here is the direct link to check this weather station.Updates On Our Changing Climate
Record warmth, extreme fire danger, tornado warnings at night in Denver, the warmest June and July on record - are these random events or are they related to Global Warming? The answer is not as easy as a simply yes or no, but overall the answer is yes!
Climate change & extreme weather are linked. Even though an individual severe weather event cannot be blamed on Global Warming, a warmer climate should bring more frequent severe weather events in the future.As temperatures warm, there is more energy in the atmosphere to create stronger storm events. This is due not only to temperature, but in many areas, to a greater amount of water vapor in the air. In the Midwest and the South, this combination of warmer temperature and higher humidity is giving late winter and early spring thunderstorms much more fuel to create tornado outbreaks.
Climate Central is an excellent resource to learn more about how Global Warming will impact conditions around the world, across the nation and in Colorado.The warmer temperatures in the western United States will be manifest in more drought and fire concerns in the decades to come. Because we are far away from large bodies of water, higher temperatures are not usually associated with increased humidity - in fact, just the opposite. Our weather is getting hotter and drier on average. The result will be more wildfires, lower reservoirs and more frequent droughts.
Here is a great interactive link showing how each state is warming.
El Nino and La Nina episodes may altered in the coming century.
Penn State has put together an excellent series on Climate Change and Ethics.
One Cold Winter Does Not Mean There Is No Global Warming
There are often comments and questions about Global Warming when unusual local weather events occur - such as snow in Las Vegas or extreme cold weather in Texas. It is important to understand that short term weather is to climate as one play in a football game is to the entire NFL season.For example, the extreme episodes of cold and snow in southern locales is due to a southern bulge in the circumpolar vortex, bringing the chilly air down from Alaska and Canada into the lower 48 states. Often, while portions of the lower 48 states are shivering, Fairbanks is enjoying very mild weather for their area. When that vortex drifts back to the north, Fairbanks is very cold again and Colorado may hit 70 degrees in January.
But The World Has Not Warmed Since 1997...
There is an often quoted issue of 1997 being the warmest year and that global temperatures have cooled since that time. This information is misleading. In 1997, the world climate was influenced by one of the strongest El Nino events ever recorded. This pool of very warm Pacific Ocean water bumped global temperatures higher. Temperatures have remained warmer than the long term average in the years since 1997 - just not quite as warm as that one spike.During this past winter and spring, the Pacific was in the midst of a La Nina - cooler sea surface temperatures. The result was a strong west to east jetstream flow over much of the U.S. that has blocked cold air from coming down from Canada - bringing record warmth to much of the country. In Colorado, we had the second warmest and the all-time driest March on record. At the same time, in Europe and Asia, the jetstream flow there brought some very cold air for the winter season along with record snows.
Frequency and Intensity of El Nino and La Nina
These periodic warming and cooling events in the ocean need to be taken into consideration over the long term, not used as singular examples of a change in the climate. However, as the overall temperature of the Earth increases, it is likely that we will see stronger versions of both El Nino and La Nina. The result will be increasingly severe individual episodes of heat and drought, storms and floods.
Frequently Used Red Herrings!
There is much discussion about the fact that the sun has by far the largest impact on our climate. The sun has certainly not been overlooked by the many experts worldwide that contributed to the most recent IPCC Assessment on climate. The periodic changes in solar output and the orbital changes are taken into account in the climate studies and modeling. In fact, the current solar output is slightly less than in previous decades - our climate should be cooling, but it is not.Another comment often heard is that CO2 is just a tiny fraction of the atmosphere. Just because CO2 is a trace gas does not mean that it is not important in the equation. Small amounts do matter - I weigh 200 pounds, but it certainly does not take 200 pounds of arsenic to kill me.The vast majority of climate scientists are in agreement that the overall warming of the planet (about 2 degrees Farhenheit since 1900), has been caused in part by mankind. This warming is due to the increase of so called "greenhouse gases" - such as CO2, methane and CFCs (chloro-fluorocarbons). These gases absorb outgoing heat from our planet and "reflect" it back to Earth. When this happens, energy from the Sun is trapped in our atmosphere and warms our climate.
The Greenhouse Effect
As often noted, the Greenhouse Effect is normal and natural, in fact if not for this effect, the Earth would be about 60 degrees Farenheit colder - a lifeless ice planet. The problem we face is that the delicate balance of temperature may be upset by a change in atmospheric chemistry.In the past 200 years (since the Industrial Revolution) the increased burning of fossil fuels has released vast amounts of carbon dioxide into the atmosphere. The concentration of CO2 has risen about 25% in the past two centuries from 280 parts per million to nearly 400 parts per million. Human activity releases about seven billion metric tons of carbon dioxide into the air every year - adding to the 750 billion metric tons that are already there.Of the 7 billion tons, only about three billion tons stays in the atmosphere; the rest is absorbed by plants and the oceans. This "carbon sink" capacity complicates the issue of global warming, because the oceans have had a vast holding capacity for CO2. The oceans are becoming more acidic, however, and there is concern that this carbon sink capacity may reach a limit.
My Personal Thoughts
I am not a climate scientist, my expertise lies in a much, much shorter timeframe. However, I spend a great deal of time on-line and at seminars with many of the best climate scientists from NCAR and other research institutes from around the world.My opinion is that we are indeed having a significant impact on the warming our climate, and this effect is making weather events more extreme. With a greater amount of energy in the climate system, there will be drier droughts, heavier rains (although more spotty), bigger winter storms and more powerful severe weather events.These events will not increase linearly, but in fits and starts. Over the decades to come, our weather will become more extreme than has been the norm since the beginning of the Industrial Revolution.
Political Science vs Climate Science
The topic of climate change has been given much political attention and in that light, there is a seemingly large controversy about what is happening and to what extent mankind is helping to cause some of the changes. In the strict world of truly peer reviewed science, the degree of controversy is not as great as some would have you believe.No doubt this is a serious issue on all sides. My greatest frustration is when it gets torn down into quick sound bites, fractured thought strings and vague conspiracy accusations between thousands of climate scientists.I am always concerned about motive...My mother was a heavy smoker in the 1960s, when there was no shortage of white coated scientists (sponsored by Big Tobacco) that claimed that there was not a definite link between smoking and lung cancer. I lost her to that disease 6 years ago.My sister spent a lot of time in tanning booths in the 1980s. Again, there were plenty of "experts" that stated the rays from the tanning beds were different and actually "good" for you. She is now fighting stage 4 melanoma.It is okay to have differing opinions - it is even a good thing, if the motives are pure science.It is very important that we study this topic with even greater effort in order to be able to take action for the future. This action may well be to use technology to bring ever increasing efficiencies to our society. Through a more efficient use of our fuels, we will be able to limit the amount of greenhouse gases released, while still enabling our complex technological society to function and thrive.We will need to urge our leaders to take action to inspire the development of new and cleaner ways to produce energy. In the unlikely event it turns out that humans are just too feeble to affect the climate, we will still be better off, as will our grandchildren, that we helped advance the technology to produce cleaner and renewable energy sources.Reducing pollution and the dependence on foreign energy sources should be something upon which all Americans can find common ground.
When the Soviet Cosmonaut Yuri Gagarin, the first human in outer space, reached the top of our atmosphere and gazed out of his small porthole, he was terrified. He was not worried about his spacecraft, he was shocked by how thin and fragile our atmosphere appeared against the cold blackness of space.Gagarin later explained that he had always been taught that we lived at the bottom of a "great ocean" of air. From his Vostok 1 spacecraft, the ocean looked more like a shallow puddle.As far as we know, out of the vastness of the universe, the planet Earth is the only place that harbors life. Someday we may find other worlds that provide an environment gentle enough to enable life to form, but for now, this is it, our lonely outpost in the corner of a galaxy.It seems prudent, patriotic and reverent that we do what we can to conserve and protect the fragile envelope of air that allows us to live on planet Earth. The legacy we leave future generations depends upon the actions we take in the coming years. Our heirs will be the judges of our success.
Mar 6, 2012:
March is typically the snowiest month for Denver with an average of just over 11-inches recorded for the month. February is the 5th snowiest of our 12 months with just over 7-inches. However, we shattered records in February thanks to the snowstorm early in the month that dumped over 2-feet of snow over parts of the Denver metro area.The snow totals in February were very impressive, and we fell just shy of the all-time snowiest February. Even the extra day in the month wasn't enough to bring the totals to the all-time February record of 22.1" back in 1912. The 2012 month will sit at number 2 all time with 20.2", most of it coming from the 15.9" of snow recorded in the first week of February.So far, our snowiest month in 2012 is look anything but. The first week has seen only a trace and the next 10 days look very quiet, signaling little if any snow potential through the first half of the month. Of course, as February proved, it only takes a well placed storm to accumulate significant snow, so it's not out of the question that March could still live up to it's reputation.
Posted: Feb 19, 2012:
Attend this week's Colorado Environmental Film Festival!The Colorado Environmental Film Festival (CEFF) is a celebration of the power of film to inspire, educate, and motivate audiences. CEFF presents thought-provoking films and dialogue that raise awareness of a wide variety of interconnected ecological, social, and economic themes. The Festival provides an experience for the audience that goes beyond passive film viewing: CEFF inspires audiences into awareness and action.The goal of the CEFF is to leave audiences with a feeling that they can be a part of the solution to environmental problems. With a growing public awareness for the environment, the Festival aims to increase this groundswell through inspiring and educational films which hopefully will motivate people to go out and make a difference in their community and around the world. CEFF involves environmental organizations through an Expo Hall, where groups can share opportunities to get involved.While the CEFF features national and international films, we also hope to highlight the works of local filmmakers and foster an interest in environmental film making through mentoring and a filmmaking forum. An important component is the opportunity for open discussion related to the films, either with filmmakers or with experts on the film's topic.The goal is to model sustainability in all areas of the film festival, including: reducing waste and providing recycling at screenings and events (with a goal of "Zero Waste"); offsetting carbon emissions; using recycled materials; encouraging the use of public transportation and carpooling; supporting local, organic, and fair trade producers.For more details, check out their website at www.CEFF.net