That's a small change in atmospheric pressure. Storms will change the pressure much faster. I doubt there is any effect on birds or wildlife around here.
Sent from Yahoo Mail on Android On Mon, Jan 17, 2022 at 9:30 PM, Hurf Sheldon<hurf...@gmail.com> wrote: Nerd question:It would be interesting to know where and by how much the East/West pressure waves cancelled each other hurf On Mon, Jan 17, 2022 at 9:39 AM John Luther Cisne <john.ci...@cornell.edu> wrote: How might the pressure wave from the Tonga eruption be experienced by birds, and how might it affect their behavior, including their dispersal? The following email comes from Lou Derry, a professor in Earth and Atmospheric Sciences. ----------------------------------------------------------------- John Cisne, Professor Emeritus Department of Earth and Atmospheric Sciences Cornell University, Ithaca, NY 14853 ----------------------------------------------------------------- From: <bounce-126242547-78860...@list.cornell.edu> on behalf of "Louis A. Derry" <de...@cornell.edu> Reply-To: "Louis A. Derry" <de...@cornell.edu> Date: Monday, January 17, 2022 at 6:09 AM To: EAS listsev <ea...@list.cornell.edu> Subject: the volcano heard round the world just for a change of pace ... You no doubt all saw the satellite imagery of the massive underwater eruption near Tonga (-175.382, -20.536) on Saturday Jan 14. If you didn’t, by all means Google it, it’s pretty awesome! One of the things you see is the shock wave propagating. There are nice images out there of the wave moving across the US as recorded by atmospheric pressure gauges. We have an Air Quality Egg (they’re made in Ithaca) at the apartment in Paris (2.3184, 48.8498) and sure enough, we see two pressure pulses. The first is the wave coming from the east, a total distance of about 16849 km. The second is the wave coming the other way around the world, 23181 km. The gauge shows an increase in P followed by a drop as the wave passes. They arrived 15 hrs 22 mins and 20:57 (approximately) after the eruption. That works out to a mean speed of 1101±5 km/yr, or Mach 0.91 (91% of the nominal speed of sound in air at 0˚C), which seems about right. Pretty amazing to see an inexpensive weather gauge pick up a volcanic explosion literally halfway around the world. The net magnitude of the first pulse measured here was about 158 Pa, or 0.047 inches of mercury. Not a lot but not too hard for a decent barometer to measure. Better instruments will probably see the wave go around the world more than once. Lou -- Cayugabirds-L List Info: Welcome and Basics Rules and Information Subscribe, Configuration and Leave Archives: The Mail Archive Surfbirds BirdingOnThe.Net Please submit your observations to eBird! -- -- Cayugabirds-L List Info: Welcome and Basics Rules and Information Subscribe, Configuration and Leave Archives: The Mail Archive Surfbirds BirdingOnThe.Net Please submit your observations to eBird! -- -- Cayugabirds-L List Info: http://www.NortheastBirding.com/CayugabirdsWELCOME http://www.NortheastBirding.com/CayugabirdsRULES http://www.NortheastBirding.com/CayugabirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/cayugabirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/Cayugabirds 3) http://birdingonthe.net/mailinglists/CAYU.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
