Wednesday, July 09, 2008

Storms of Summer

I half expected a tornado to pop out of this cloud last night, and fortunately that didn't happen. I had a meeting in the evening and was driving back to the cabin, knowing I was just a step or two ahead of the storm. Then I got out of the car to take a few photos. As a result, when I did get back to the cabin a few minutes later, I only just pulled into the lane when the sky opened up, and a torrent of rain kept me from getting out of the car. It was like someone dumped a huge bucket right on top of Roundtop. I had over one inch of rain in 15 minutes, and I was lucky. Several miles away, they ended up with around 3 inches, but several miles to the north not a drop fell.

I've been working on the fall issue of Hawk Migration Studies, the journal published by the Hawk Migration Association of North America, and this week while editing the eastern flyway report, the flyway editor wrote that he lamented what he called the "new weather." I'd not heard this phrase before, but the more I think about it, the better I think it's a good one.

Back in the day, more than 20 years ago when I first started hawkwatching, we didn't know nearly as much as we do today about weather and migration. But, even then experienced hawkwatchers had a tendency to call in "sick" at work and show up on a hawkwatch in the fall the day after a cold front blew through, bringing with it northwest winds. For some years now, the problem has been that fall now rarely brings those sweeping cold fronts, and as a result patterns of migration have changed.

The flyway editor was noting that traditional hawkwatches that used to get many thousands of hawks (and other avian migrants) now rarely get those excellent flights. Instead, because the weather and wind patterns have now shifted, some ridge or hill that never saw much of a flight before is suddenly the stellar site from which to watch migration. Migration is no longer funneled by wind patterns past the traditional migration sites. Instead, migration now often follows a broader front or ends up on the coast or sometimes runs more inland than before, and these new areas are suddenly the hot spots.

I was thinking about this "new weather" last night when this storm clobbered my little corner of the world. Summer thunderstorms are not a new phenomenon here, but what is different is that the storms pass almost every night. Further, the storms are more localized. Instead of a storm that hits the region as a whole, these intense cells suddenly pop up, seemingly out of nowhere, and douse a small area with lots of severe weather. Only a few miles away, the storm isn't even present. Weird, eh? I guess it's just the new weather.

6 comments:

John said...

That's interesting. I wonder what is causing the shift in wind patterns.

Carolyn H said...

John: The assumption is that climate change related to warming is the culprit. I don't know that there's been anything definite pointing to that, though. The shift in weather patterns began to be noticeable perhaps 10 years ago, and then we blamed it on the increase in buildings and parking lots that perhaps created more thermals than do fields and open land.

Carolyn H.

Cathy said...

I had one those pop up T-storms yesterday. It pour at the library but 4 miles away at my house. Nothing!

It's a shame that the weather has really goof up migrations of the hawks. But at least they are adapting to it.

David McCauley said...

in terms of climate change we are generating conclusions based on fractions of a microsecond. Why not address habitat loss....(something real) you cut down the trees and the broad-winged hawks will be forced to establish new nesting grounds and create a new flyway. the eastern flyway may diminish as other flyways grow. just a thought. good birding.
David McCauley
Tlacotalpan, Veracruz Mexico

Carolyn H said...

David: Thanks for visiting my humble blog. Someday, I will make it to Veracruz! You may be interested in a report from Derby Hill, New York, of 40 northbound Broad-winged hawks this past Tuesday--a very odd time for that and a very interesting report!

Carolyn H.

Carolyn H said...

David: Thanks for visiting my humble blog. Someday, I will make it to Veracruz! You may be interested in a report from Derby Hill, New York, of 40 northbound Broad-winged hawks this past Tuesday--a very odd time for that and a very interesting report!

Carolyn H.