Showing posts with label snow. Show all posts
Showing posts with label snow. Show all posts

31 January 2014

The End Has Come, But This Is Not The End


Me Wednesday afternoon up on the Tug Hill after digging out one of our instruments. The snow was 4 ft deep here with 6 inches of ice underneath.
(Photo courtesy Peter Veals)

Well, OWLeS is officially over as of this past Wednesday. Most of us have packed up and returned home following a grueling 6 weeks of field research. But I can say without a shadow of a doubt that it was worth it, and the data that were collected during the project are going to be analyzed for years to come by dozens of researchers and grad students. OWLeS was extremely successful in so many ways! The data were great, the snow storms were borderline epic at times, and just about every scientist involved got the kind of data he/she was looking for. 

All in all, we studied 24 lake-effect events in 43 days. Two of these events dumped 5+ feet of snow at some locations in just a few days. The King Air flew 21 flights, 7 of which I was on. More than 100 people participated from 8 universities, two National Weather Service offices, and one research center, including 15 main scientists and about 50 undergraduates. At least 75 different weather sensors and instruments were used, including 8 radars, 200 or more weather balloons were launched, thousands of snowflake photographs were taken, and countless snow measurements were made. 

Ultimately, it was a great project. As my advisor said, "fewer than 1 in 10 winters are this good for lake-effect systems". We picked the right year to do this study, and it certainly paid off. Here are a few other interesting quotes from some of the OWLeS scientists:

"I will say this has been, by far, the most challenging field campaign that I have been involved with."

"Never in my wildest dreams did I imagine we'd have a field season as active as this!"

"...what can only be described as an epic period of field data collection..."

I hope you have enjoyed following this blog as much as I have enjoyed updating it. I hope you've learned a bit about the King Air. I hope you've learned something about how scientific field projects are done. Perhaps most importantly, I hope you've gained a new appreciation for how fascinating science and, in this case lake-effect snow, can be. Otherwise, this is probably my last post in this blog. Thanks for following, and stay curious my friends!

P.S. If you are a Wyoming middle or high schooler who found this blog through the Science Posse, you might just see me at your school sometime this spring with the Posse if we come visit!

30 December 2013

The University of Wyoming King Air


As promised, here is just a little bit about the airplane I've been flying in during the OWLeS project!

I've mentioned in previous posts that many different types of research tools and instruments are being used in OWLeS to make measurements of the atmosphere while lake-effect snow storms are taking place. The main contribution from the University of Wyoming is our own research aircraft, the King Air. This means that the majority of the work I am doing during the project is related to the aircraft, which includes flying on it during IOPs!

The Aircraft Itself
The King Air is a small twin-engine airplane outfitted with various meteorological instrumentation and has been used in many research projects over the last 36 years. It has been all over the United States, down to the Caribbean, to Finland, and most recently to England, just to name a few locations. Most of the instruments or sensors on the airplane make fairly common measurements, like temperature, air pressure, wind speed/direction, and humidity. There are other less-common sensors that measure the size of cloud droplets and the amount of liquid water in the air.

06 December 2013

What is Lake-effect Snow, and Why Study It?

If you live near the Great Lakes, and especially in upstate New York, you will have most likely heard of lake-effect snow before. But elsewhere, the term is probably foreign to your ears. So what is lake-effect snow? And what is so special about it? I personally think it is a very cool weather phenomenon, although the general process behind it are relatively simple.

Lake-effect snow is simply snow that forms over a lake (in our case, Lake Ontario in the Great Lakes) due to the difference between the temperature of the lake surface and the air directly above it. Lake-effect snow occurs at large lakes all over the world, but is perhaps most prominent over the North American Great Lakes. In late autumn or early winter, before the lakes freeze over, very cold airmasses from Canada will occasionally swing down over the Great Lakes, bringing frigid temperatures to the region. The air might be 10-20 degrees Fahrenheit, while the lake water temperature might still be 40-50 degrees. This creates a situation where the lake water is much, much warmer than the air flowing over it.

Most of us know that warm air rises as long as it is warmer than the air around it. As the cold air flows over the much warmer lakes, the air in contact with the water will warm due to conduction and will also pick up lots of moisture from the lake itself. This creates a layer of relatively warm, humid air right above the water which eventually begins to rise through the cold, dry air around it. Just like with summertime thunderstorms, this rising warm air eventually cools off to the point that condensation can occur, forming a cloud, and eventually snow. If the warm air is rising fast enough, and contains enough moisture, then the snow that forms in the cloud can become very heavy in a very short period of time. This is illustrated in the photo below.