During some periods, most of the reflectivity detected by NEXRAD radars is biological - primarily birds, bats and bugs. The images above display composite reflectivity obtained from the NMQ web portal May 17, 2010. The left panel shows a reflectivity map before applying quality control to remove non-meteorological effects. The date is near the peak of nocturnal spring migration of songbirds in the northern part of the U.S.; insects and probably bats also contribute to the radar return. The lower panel shows the same data after quality control. The underlaid grey shading denotes terrain elevation with lighter colors repesenting higher elevations.
image search pulls up alot of similar maps and they all say "birds"What are these blue splotches?
In the video above, posted a couple years back by Christopher Wood, blue stippled circles bloom and spread over the continental U.S., all coinciding with the half-hour after local sunsets. Those circles are birds—this is a pattern typical of large groups of birds taking off to resume migration.
Many species of birds choose to migrate at night. Unfortunately for most bird watchers, millions of birds pass undetected through the night sky in the spring and fall as they make their journey between their breeding and wintering grounds.
In 1952, an organized, continent-wide network of 1,391 birders and astronomers performed counts of nocturnal migrant birds crossing the full moon (Lowery and Newman, 1966). From the 1st to the 5th of October that year, observers across North America manned 265 observation points in three Canadian provinces and every state except Alaska, Hawaii, Maine, Nevada and Utah. A total of 35,407 birds silhouetted against the moon were counted. Data were then compared with weather patterns across North America to discover relationships and patterns that affect the movement of birds.
Some keywords for searches: Aerofauna, Bioscatter, biological scatterers.
LEFT: Radar captures this snapshot of bird migration across the eastern and central United States on April 28, 2004, at 23:02 CDT. Precipitation appears over southern Texas and across parts of the West. Individual radars detect birds out to a certain range, shown as circular patterns of echoes. The overall pattern indicates that birds are migrating as a relatively continuous layer throughout the east-central United States.
RIGHT: NEXRAD (NEXt generation RADar) is also known as Weather Surveillance Radar, 1988 Doppler (WSR-88D). Pictured is the tower that houses the antennae inside the radome (white sphere).
Tonight, KGSP has a new one for the "weird things seen on radar" file...bats, and lots of them!
Our radar is in a more sensitive mode ("clear air mode") right now, so it can pick up more than just rain. It's bats leaving roosts tonight!
+mike roma The radar image is a mosaic. Each ring in spring and fall is individual radars detecting stuff in the air around the radar, that is why the rings occur in the same place every night. The spring and fall green nocturnal radar blobs are the annual nocturnal migration of millions of birds between north and south America. Notice that in the spring the blobs are ahead of cold fronts and in the fall they are behind the cold fronts. Birds are using the south winds to go north in the spring and north winds to head south in the fall.
Primer on national composite radar for tracking bird mass movements with some archive loops so you can compare the different times of year and blobs relative to weather patterns:
https://people.mbi.ohio-state.edu/hurtado.10/US_Composite_Radar/
Type bird migration radar into Google Scholar to learn more than you may care to know about tracking bird migration with radar. http://scholar.google.com/scholar?q=bird+migration+radar&hl=en&as_sdt=0&as_vis=1&oi=scholart&sa=X&ei=Ua4vVYWYMPSHsQSgn4GoDQ&ved=0CDIQgQMwAA
Or visit the website for Clemson University's radar ornithology lab. http://virtual.clemson.edu/groups/birdrad/comment.htm
Read the above posts. Yes, millions of birds migrate at night each spring and autumn.so these radar blooms the blossomed around nine pm like every night , and that are still blooming at 2am, are migrating birds and bats? highly unlikely considering nothing is migrating and there isnt swarms of bats all night long.
No, again read the links above. Many, in fact most, species of land birds migrate at night.only geese and cranes migrate at night
http://www.pressherald.com/2011/10/02/watching-and-listening-as-birds-migrate-at-night_2011-10-02/
The majority of land birds migrate at night. These include cuckoos, flycatchers, warblers, vireos, thrushes, orioles and sparrows...
Migration at night has at least three advantages. Birds do not have to worry about falcon or hawk attacks. Second, the air in the atmosphere is usually less turbulent than during the day. Lastly, the air is cooler at night.
ionization of the atmosphere for geoengineering maybe, migrating birds it is not!
so these radar blooms the blossomed around nine pm like every night , and that are still blooming at 2am, are migrating birds and bats? highly unlikely considering nothing is migrating and there isnt swarms of bats all night long.
only geese and cranes migrate at night and it isnt in a circular blob, the bloom starts at the radome and goes outward in a circle
ionization of the atmosphere for geoengineering maybe, migrating birds it is not!
These radars show what is happening at relatively low altitude, where rain is falling (and birds are flying). If the atmosphere was being "ionised" then it would be conductive, and you'd see obviously effects such as overhead power lines arcing to ground. Have you got any evidence for this? And are you suggesting that the numerous scientists who track migrating birds by radar are mistaken?ionization of the atmosphere for geoengineering maybe, migrating birds it is not!
so the return to the radar if it were geese would show extreme hail, bats would be golf ball sized hail...
I'm not sure how to parse this - perhaps you could clarify?so from the radome in valley nebraska west there are no bugs birds or bats, but east of that there is so many that i personally standing near the radome cannot see or hear them?
but east of that there is so many that i personally standing near the radome cannot see or hear them?
Quantifying non-breeding season occupancy patterns and the timing and drivers of autumn migration for a migratory songbird using Doppler radar
Authors
- E-mail address: alaughli@unca.edu
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- Dept of Environmental Studies, Univ. of North Carolina Asheville, Asheville, USA
- Dept of Ecology and Evolutionary Biology, Tulane Univ., New Orleans, USA
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- College of Information and Computer Sciences, Univ. of Massachusetts, Amherst, USA
- Dept of Computer Science, Mount Holyoke College, South Hadley, USA
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- Dept of Ecology and Evolutionary Biology and Lab of Ornithology, Cornell Univ., Ithaca, USA
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- Dept of Ecology and Evolutionary Biology, Tulane Univ., New Orleans, USA
- First published: 14 January 2016Full publication history