Thank you to everyone who has helped address the issues of the NM migrant die-off, the surprising weather, and some effects of climate change. Here’s a very generalized view and analogy about weather, global warming, and climate change which I have found helpful:
Sunlight heats the earth the most where it hits most directly and for the longest time during the day. That includes the tropics, or low latitudes, where midday sun is very direct, and where daytime is always about 12 hours. And it includes whichever hemisphere is tilted toward the sun and having summer where, as you increase in latitude going toward the polar regions, the hours of daylight increase to 24 although directness of the sun decreases. The average temperature of the earth has been staying fairly stable within a narrow range for years and years. A stable temperature means that as much heat has to leave the earth as was provided by the sun’s warmth. That heat is radiated back to outer space from the places which are not being heated up: wherever it’s nighttime, plus wherever the sun strikes at at too low an angle to effectively provide much warmth - in early morning, late afternoon and higher latitudes. Wind, at its most basic, is caused by temperature changes at the earth’s surface which warm or cool the air, changing the air’s density and pressure. Denser air falls, and the air moves to even out the pressure. And the air redistributes heat as it moves. On a very large scale, that heat redistribution takes heat from the warmer places to the colder places, but the wind has many eddies, so that what happens locally or regionally may be different. [There are also huge effects from water which I’m ignoring here: Part of the earth’s surface, the ocean, moves and transfers a great deal of heat energy in major currents such as the Gulf Stream. Ice & snow reflect sunlight back into space. Clouds also act as reflectors on top but as insulating blankets below. Water absorbs heat as it evaporates or melts but gives off heat as it condenses or freezes.] My analogous situation is a pot of hot water on a stove such that the lid is off, the water has been brought to a boil, so it is thoroughly warmed, and the flame has been reduced enough that the water is no longer boiling, but it’s in a steady state where there are steam bubbles forming on the bottom which disappear before reaching the surface. The source of heat is the flame below, analogous to the sun. The heat, via the water, eventually goes into the room, our equivalent of outer space. If you look down at the water you should be able to see places on the surface where there are upwellings of warmer water rising. The water doesn’t rise everywhere at once, and the water is descending in between where it is rising. The pot itself is like the surface of the earth, warmer right over the flame (where sunlight is direct and prolonged) and cooler at the rim (everywhere else). The movements of water in the pot are like the weather on earth. The heat comes in, it gets moved around by the weather in a general pattern with lots of smaller scale differences, and the heat leaves, while the overall temperature remains fairly even. Now, suppose that, without changing the low flame, you partially cover the pot with a lid. It’s now a bit more difficult for the heat to escape, so the water temperature rises to a new stable level, and you may even get the water to boil again without increasing the flame. Also those convection currents in the water get stronger - both the hot currents going one direction and cooler currents going the other direction. The lid partially covering the pot is the equivalent of adding greenhouse gases to our atmosphere. The result is a warmer average temperature, and also stronger weather patterns, both warm winds and cold winds, and stronger storms (with lots of water evaporating, condensing, freezing & melting) helping to redistribute heat as well. What happens at any particular location on earth is apt to be different from previous patterns, more extreme, more violent, and more variable. We can’t rely as much on our reassuring decades of weather records (the previous climate for any location) for what to expect anymore, because we have changed the atmosphere so that the system is more energetic. As a reward to birders who slogged through my weather & climate paragraphs, and as a distraction from the terrible migrant mortality out west, and as an attempt to redeem an otherwise non-bird post: An adult Junco showed up at my feeders yesterday and today, which to me is a sign of autumn. An immature junco was briefly here at the end of August in a streaky gray plumage which my 2nd edition Sibley guide did not depict. A male Rose-breasted Grosbeak first showed up at my feeders on 24 August and I assume it’s the same bird I’ve seen several times since, including today. He has been molting into a plumage which, again, my 2nd edition Sibley guide did not depict. - - Dave Nutter > On Sep 16, 2020, at 8:41 PM, John Luther Cisne <john.ci...@cornell.edu> wrote: > > Record cold over North America is indeed consistent with global warming. It > is a regional consequence of the global phenomenon. > > To explain it simply (as I was supposed to do in the elementary course I > taught of years and years, “Evolution of the Earth and Life”), the principle > of the thing is that Arctic Basin warms not only by importing warm air from > the south, mainly over oceans, but also by exporting cold air to the south, > mainly over continents. Export of air from the north makes space for import > of air from the south, so to speak. For now, at least, the export of cold > air from the Arctic is concentrated over North America. > > Certain of my colleagues in the Department Earth and Atmospheric Sciences > will be able to give everyone a far better and more detailed explanation. > > > From: <bounce-124948208-77975...@list.cornell.edu> on behalf of "Kevin J. > McGowan" <k...@cornell.edu> > Reply-To: "Kevin J. McGowan" <k...@cornell.edu> > Date: Wednesday, September 16, 2020 at 8:03 PM > To: david nicosia <daven1...@yahoo.com>, Peter Saracino > <petersarac...@gmail.com>, Jody Enck <jodye...@gmail.com> > Cc: "atvaw...@gmail.com" <atvaw...@gmail.com>, CAYUGABIRDS-L > <cayugabird...@list.cornell.edu> > Subject: RE: [cayugabirds-l] New Mexico Mass Motality > > “Record cold of this magnitude is not consistent with global warming. “ > > Why not? Global warming doesn’t mean warming happens all over the globe > evenly. I’ve been watching our area in the northeast for the last decade, > thinking mostly about Snowy Owl incursions, and I’ve noticed strange changes > in the distribution of cold across the arctic, perhaps changes in the “polar > vortex” that seem to isolate the NE as a cold spot while Alaska warms up. The > last ten years have shown Ithaca regularly with winter temperatures lower > than Nome, Alaska. That isn’t right. > > Global warming at the poles doesn’t mean every place warms up, it means that > the consistencies of weather patterns we could count on could be disrupted. > Colder Ithaca winters and heat waves in Alaska are totally consistent with a > global warming scenario. Freak arctic blasts into the rockies while the north > pole melts also points to something freakishly abnormal happening, totally > consistent with global warming. > > Kevin > > > From: bounce-124948138-3493...@list.cornell.edu > <bounce-124948138-3493...@list.cornell.edu> On Behalf Of david nicosia > Sent: Wednesday, September 16, 2020 7:46 PM > To: Peter Saracino <petersarac...@gmail.com>; Jody Enck <jodye...@gmail.com> > Cc: atvaw...@gmail.com; CAYUGABIRDS-L <cayugabird...@list.cornell.edu> > Subject: Re: [cayugabirds-l] New Mexico Mass Motality > > The western U.S has a history of extreme temperature changes. This event > ranks number 3 for the biggest temperature swing in history and it occurred > during fall migration. Most of the other big swings in temperature > occurred in the winter. What is dramatic is how cold it got and the early > snows that fell. Temperatures in parts of the Rockies fell to 9F with winds > over 50 mph. That is insanely cold for so early in the season. The Arctic > high pressure that came across the Rockies has denser and heavier air which > flows downslope into California, and Oregon warming by compression leading to > high winds and VERY dry conditions. This fuels the tremendous fires. So in a > sense it is the brutal unseasonable cold air that is the real cause of the > conditions that caused the fires. I assume the fires, combined with > temperatures in the 80, 90s and 100s dropping to the teens 20s and 30s in > many areas in the Rockies with early snows was too much for many birds to > handle causing the high mortality rates. I have read that people are blaming > climate change on this. I don't see it because it is the intense cold that > really fueled the fires in CA and OR and probably had a negative effect on > the birds. Record cold of this magnitude is not consistent with global > warming. > > > On Wednesday, September 16, 2020, 05:18:09 PM EDT, Jody Enck > <jodye...@gmail.com> wrote: > > > Thank, Pete, for passing along the Guardian article. Additional information > has been forthcoming recently. Hypotheses include movements related to smoky > conditions in some states, coupled with those weird temperature swings > recorded last week (90 to 100 F one day and below freezing, with snow, the > next day). Seems less likely to be a nefarious even (e.g., poisoning) than > something more likely caused by challenging environmental factors. > > I hope more information comes out soon. > > Jody W. Enck, PhD > Conservation Social Scientist, and > Founder of the Sister Bird Club Network > 607-379-5940 > > > On Wed, Sep 16, 2020 at 5:03 PM Peter Saracino <petersarac...@gmail.com> > wrote: > https://www.theguardian.com/environment/2020/sep/16/birds-falling-out-of-the-sky-in-mass-die-off-in-south-western-us-aoe > > > On Tue, Sep 15, 2020, 6:47 PM Tom <atvaw...@gmail.com> wrote: > I just learned of the mass mortality of migrating birds in New Mexico. I > read a CNN report. Is there any new information on the cause? They’re > talking hundreds of thousands, even millions. > > Tom V > > Sent from my iPhone > > > -- > > 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/ > > -- > > -- > 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: > 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: > 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/ --
