 Radar image taken July 2015 NWS Norman, OK of grasshoppers and beetles over Qaunah, TX. DISCUSSION: When observing the radar at night, large circles of reflectivity usually surround the radar scan area. It is likely that this reflected feedback from the radar is ground clutter, although in other cases you might see something else. When there isn’t any active weather within a radar coverage area, the local radar is set to a slower antenna rotation which causes the radar to have a finer resolution and heightened sensitivity. This setting is called “clear air mode”. During this mode of operation, the radar will pick up reflected ground clutter from mountains, buildings and tall objects as well as clear air echoes such as dust particles, light drizzle, air mass boundaries and fronts. Clear air mode is also used by scientists to pick up on certain echoes that many wouldn’t think of being a possibility. These specific clear air echoes are birds and insects. This has been beneficial to scientists who have used clear air mode to study bird and insect migrations for years.
When the radar is in clear air mode, it has an advantage of picking up on small objects such as insects and birds. This is because of its increased sensitivity and resolution. When birds or insects cluster together in larger groups, they become increasingly visible by the radar. The more birds and insects in one area, a higher reflectivity is shown in the radar image. Scientists can determine the difference between bird and insect reflectivity in a multitude of ways. For birds, it depends on the time of day. Most species of migrating birds continue their travel at sunset and fly through most of the night before landing at sunrise. Using radar velocity imagery, scientists can also decipher between birds or insects by comparing their movement to the prevailing winds. If the reflectivity moves against or faster than the wind, it could be birds. It is challenging to determine if the reflectivity is caused by insects because they fly with the wind rather than against it. For insects, it depends on the time of year and location more so than the time of day and speed. Many insects in the spring and summer tend to swarm near rivers, lakes, fields and ocean shores where they hatch, use up resources and gather to reproduce. In the image above, a radar signature posted by NWS Norman, Oklahoma shows grasshoppers and beetles as they move over agricultural fields in Quanah, Texas on July of 2015. The radar shows the movement of these insects to be northeast in the direction of Oklahoma. It is typical for grasshoppers and beetles to migrate from one area to another using up resources and then moving on to find more food elsewhere. Grasshoppers are especially one of the most burdensome migratory insects to agriculture. They eat most of the grain, cereal, tomato and onion crops until there is nothing left. Radar is used in detecting density, location, direction, and speed of birds and insects. A study done by Dr. Sid Gauthreaux and Carroll Belser was able to quantify bird migration using radar reflectivity by interpreting magnitude of bird migration in terms of radar values measured in dBZ (decibels of Z, where Z represents the energy reflected back to the radar). Their findings are used today as a guide to scientists who record and predict migrating bird patterns. The guide is established as follows:
Radar has been very beneficial to the science of studying bird and insect migration just as much as it has been for meteorologists who study and forecast the weather. One would not expect, aside from the normal radar imagery of precipitation in large and small storms, that they would have the ability to see insects and birds as well. Clear air mode allows for this and is a very useful tool in furthering scientific discoveries. For more interesting weather related topics click on the link below: https://www.globalweatherclimatecenter.com/observations ©2018 Meteorologist Alexandria Maynard
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DISCUSSION: There is no debate that the first "true round" of severe weather has now arrived across the Central United States over the past 24 to 48 hours. This multi-day severe weather event has been predominantly characterized by impressive storm structure, impressive lightning displays, and very heavy rainfall bursts anywhere in the path of the more intense convective storms. However, a very important aspect of severe weather which is quite often overlooked is the impact of how modern satellite imager observations have revolutionized the ways in which scientists study, analyze, and forecast both current and past severe weather events.
There is no debate across the atmospheric science forecasting and research communities that GOES-East satellite imagery has completely "changed the game" in terms of how meteorological forecasters and/or researchers analyze and study the atmosphere. More specifically, the GOES-East Advanced Baseline Imager (ABI) 16-channel platform facilitates incredibly high-resolution analyses of storms on very small scales. One such example can be found with the GOES-East 1-minute visible satellite imagery on 2 May 2018 as storms fired up across many parts of Kansas and also across northwest Oklahoma. In the aforementioned 1-minute visible satellite imagery attached above, you can see how there appears to be a "bubbling" phenomena occurring near the center of the cloud deck associated with the blossoming convective storm complex. This "bubbling" effect is a visual manifestation of what are known as "overshooting tops." Overshooting tops are an indication of the fact that there is a particularly intense region of a given thunderstorm wherein the updraft is so strong that it breaks through the upper-most part of the thunderstorm. This point at which the updraft breaks through the top of the given cloud deck is what is visually observed as the "overshooting top" part of the thunderstorm. Therefore, it goes without saying that when severe thunderstorms develop these "overshooting tops" features, that is not a time that you want to be under or in the path of such a storm since it would have that much of a greater potential to develop heavier rainfall and even hail at times. To learn more about other interesting stories pertaining to weather observations, be sure to click here! © 2018 Meteorologist Jordan Rabinowitz
DISCUSSION: Earlier this month, the National Weather Service in Austin/San Antonio tweeted a radar image of a colony of bats outside of the cities of Concan and Knippa in Texas. Where did these bats come from and how can we see them on radar?
Texas is home to some of the largest bat colonies in world. This includes the largest known bat colony at the Bracken Cave Preserve and the largest urban bat colony at the Congress Avenue Bridge in Austin. Just a few hours away from these two colonies is the Frio Bat Cave, which is where the bat colony shown in the above radar imagery resides. In April and May, it is common to see swarms of hungry pregnant mother bats leaving their caves looking for food just after sunset with waves of bats leaving for 2-3 hours. In early June, the baby bats are born, meaning that the swarms of bats leave their caves later in the evening. In late July/early August, bat season reaches its peak and these bat swarms will continue to be seen until as late as November. How exactly can these bats be seen from weather radar? Radar sends out signal that hits an object and is then reflected back to the radar at varying strengths depending on the size of the object. Usually, the signal received back is reflected from precipitation. However, other objects such as smoke plumes, insects, birds, and bats, can also reflect signal back to the radar. This is why you can get what looks like precipitation showing up on the radar even when there is none occurring in that area. How do we know a radar signature is bats and not actually rain or another source? A bat signature on radar will show up first as a sudden circle that quickly spreads outwards in subsequent frames of the radar until the bats have all dispersed. These signatures are also typically found in the evening when bats leave their caves to find food. If you live in an area with an active bat colony, you may just be able to spot these animals leaving their caves on radar! To learn more about other neat observational stories both directly and indirectly related to atmospheric science, be sure to click here! ©2018 Meteorologist Stephanie Edwards  Discussion: An important technique to estimate the strength of tropical cyclones is known as the Dvorak technique. The Dvorak technique, developed by Vernon Dvorak is a satellite-derived system to estimate storm strength solely based on visible and infrared satellite imagery. The system uses cloud patterns visualized through satellite imagery and can then be used to indirectly measure wind speed and central pressure. Today the Dvorak method is used mainly as verification to measure wind and pressure. This important technique is even used by the National Hurricane Center. What makes this system useful and accurate is because storms with approximately similar intensities were found to contain similar cloud pattern identified on satellite imagery.
 DISCUSSION: Earlier this month, it was discovered that the Geostationary Lightning Mapper (GLM) on the GOES-East satellite had captured some of the first satellite imagery of a phenomenon known as gigantic jet lightning. But what exactly is gigantic jet lightning and how did the GLM “see” it?
Gigantic jets are a type of upper atmospheric lightning, also known as transient luminous events (TLEs). While most TLEs lack many of the characteristics of the lightning we usually see in thunderstorms, gigantic jets are different in that they are connected to the electrical discharges that cause “typical” lightning. In a thunderstorm, a build-up of electrical charges within the cloud leads to the formation of lightning. While the exact mechanism behind this build up of charges is debatable, what is known is that when enough charge is built up, energy is released from the cloud in the form of lightning. Normally we think of lightning as flashes within or between clouds, or as strikes between the cloud and the ground. With gigantic jets, the electrical discharge exits from the top of the cloud into the ionosphere, reaching upwards of 50 miles into the atmosphere. Gigantic jets have been captured in videos and photography for years, but it was only recently that they have been captured on satellite imagery. The GLM on the GOES-East satellite continuously maps and detects lightning over the Americas and surrounding oceans. Lightning strikes and flashes emit light through the top of the cloud, which is detected by GLM and shown in satellite imagery. Since gigantic jets are electrical discharges emitted through the tops of clouds, they too would be detected by the GLM. Furthermore, they would show up even brighter and more intense on satellite imagery than typical lightning flashes, since what is being detected in this case is the electrical discharge itself rather than just the light from the flash emitted through the cloud. Satellite imagery provided by the GLM can be used to help us further understand gigantic jets and other lightning phenomenon. To learn more about other neat observational stories both directly and indirectly related to atmospheric science, be sure to click here! ©2018 Meteorologist Stephanie Edwards 
DISCUSSION: During the course of a given year, there is no question that there is an abundance of evidence proving that Earth effectively has a "living and breathing system" which is in a state of constant flux. This is perfectly illustrated by the fact that as shown in the looped real-color satellite imagery attached above, Earth's oceans and foliage operate as a "filter" to help purify the air surrounding Earth (even in the presence of continued fossil fuel consumption). Thus, Earth's oceans and foliage act as a balancing force in Earth's ability to clear out a solid percentage of man-based consumption of fossil fuels which underlines the importance of protecting the Earth's forests and Earth's oceans. Attached below are some exact excerpts from the actual article which was published by NASA and discusses some of the core principles of this research.
"Carbon naturally cycles through Earth’s environments. Trees and other plants take up carbon dioxide and turn it into the building blocks of roots, stems and leaves. Some of that carbon stays in the soil as the vegetation dies and gets buried. Some is released back into the atmosphere as carbon dioxide through plant respiration, and both carbon dioxide and methane — another potent, carbon-based greenhouse gas — can be released through decomposition, land clearing and wildfire. The ocean absorbs carbon dioxide from the atmosphere, and the tiny water-dwelling plants called phytoplankton take up the gas as well. Over many millennia, the pace of carbon cycling is governed by volcanic emissions and weathering of rocks. For most of human history, carbon has been in a more-or-less steady cycle. This cycle has been thrown off balance as people burn fossil fuels — carbon that has been long buried underground as oil, gas and coal — and as forests are cleared and soils are turned for agriculture. All of these contribute to increasing carbon emissions. While the amount of carbon dioxide emissions that ecosystems absorb from the atmosphere each year varies quite a bit, the fraction in the long run has averaged out to about half. More carbon dioxide and methane in the air means warmer global temperatures. Warmer temperatures can disrupt some ecosystems and impact their ability to absorb more and more carbon. An even more imbalanced carbon cycle will cause greater variability and consequences that are not yet fully understood." To learn more about this particular story as published by NASA, click on the following link: www.nasa.gov/feature/goddard/carbon-climate. To learn more about other neat stories surrounding observations in geo-science, be sure to click on the following link: https://www.globalweatherclimatecenter.com/observations. © 2018 Meteorologist Jordan Rabinowitz   DISCUSSION: Over the past 48 to 72 hours, the Mid-Atlantic and Northeastern regions of the United States have experienced the brunt of a potent Nor'easter. More specifically, this powerful winter storm slammed those areas with strong winds, heavy precipitation (with some locations receiving rain or snow depending on the progress of the storm itself as well as a given location's proximity to the coastal sectors). In addition, closer to the coast, this storm unleashed incredibly large and persistent wave action which ultimately led to major coastal erosion/damage in cities such as (but certainly not limited to) Scituate, Massachusetts where there was tremendous infrastructural damage. Thus, this storm effectively devastated many coastal towns and cities which in some cases may take days or even weeks to fully recover.
Having said that, in the wake of this recent coastal storm's passage, the nation is simply left with scenic low/mid-level satellite imagery containing features most commonly referred to as cloud streets across a good portion of the far Western Atlantic Ocean. Cloud streets are long-distance cloud features which develop as a direct result of cold air moving over relatively long-distances of warmer water (i.e., generally distances of at least 50 to 100 nautical miles). During this process, the colder air parcels are modified by the warmer water they are moving over (in this particular case being the passage of the colder air over the warmer waters of the Gulf Stream off the East Coast of the United States). As these colder air parcels are modified by the warmer water, the air parcels condense into low-level clouds which naturally undergo rising motion due to the warmer air parcels rising higher up into the atmosphere. These low/mid-level clouds move in an outward direction in accordance with the prevailing wind direction in the lowest levels of the atmosphere. Thereby, producing what is visibly observed as cloud streets on both visible and infrared satellite imagery channels. To learn more about other neat observational stories either directly or indirectly connected to meteorology, be sure to click the following link: https://www.globalweatherclimatecenter.com/observations! © 2018 Meteorologist Jordan Rabinowitz 
DISCUSSION: Over the past 24 to 48 hours, the world watched as a historical extra-tropical low-pressure system (more commonly referred to during the Winter-time months as a Nor'easter when positioned along the East Coast of the United States). During the course of the lifetime of this historic nor'easter, there were prolific impacts inflicted across the eastern half of the United States all the way from central/northern Ohio to the Mid-Atlantic and the Northeast regions of the United States. s this began its trail of impacts across parts of central and northern Ohio, more than 200,000 people were left without power within the first few hours of impacts from this powerful Winter storm. The primary power outage catalyst ac as a result of heavy wet snowfall accumulating rather quickly along with blustery winds which aided in the process of downed trees and consequently downed power lines which took out power for many people across northern and central Ohio.
As the storm began to transfer its energy from the Central United States to the East Coast, havoc was quickly unleashed all the way from Virginia and North Carolina to northern New England. This came as a result of a combination of large amounts of heavy/wet snowfall along with incredibly strong winds (in some cases up to and over hurricane force) which subsequently led to widespread power outages across more than 6 states across the Northeast United States. In addition, along coastal regions there was tremendous damage caused by major coastal flooding via a very potent storm surge all the way from coastal Maine to coastal New Jersey. Hence, this was a very far-reaching coastal low-pressure system which ended up being one for the books and will be remembered by many for a long time to come. What made things even more interesting was the latter interaction which occurred between what remained of the powerful coastal low and an upper-level low pressure system positioned over Hudson Bay, Canada. This interaction effectively involved a symbiotic upper-level channel of poleward moisture and energy transport which often with extra-tropical cyclones later in their lifetime as they begin to breakdown and dissipate. However, in the case of this particular Winter storm, there is a blocking high-pressure system positioned to the north of low. Therefore, due to the clockwise flow of the wind streams around the blocking high-pressure system, this facilitated an effective northward moisture transport during the course of the day on Saturday. This process is reflected by the animated infrared satellite imagery attached above. To learn more about other neat stories pertaining to various global meteorological observations, click: https://www.globalweatherclimatecenter.com/observations! © 2018 Meteorologist Jordan Rabinowitz Reflecting on the Historic Launch of the GOES-S Satellite (credit: Meteorologist Jordan Rabinowitz)3/2/2018  DISCUSSION: Earlier on the evening of Thursday (03/01/2017), Cape Canaveral, Florida was the center of focus across the global scientific and non-scientific communities alike. This was a direct result of the fact that Thursday evening marked the launch of NOAA's second next-generation advanced weather satellite imager in GOES-S. The successful launch of the GOES-S satellite marked the continuance of the second of 5 to 6 next-generation satellite imagers which will end up forever changing and revolutionizing the way in which atmospheric scientists visualize and study the atmosphere. It is an incredibly exciting moment in global weather history since when GOES-S becomes fully operational later this year, it will officially pair up with its current operational sister satellite in the form of GOES-16 (formerly GOES-R at the time of its launch back in late November of 2016).
The pairing of having both GOES-16 and GOES-17 at work together will help to further bridge the gaps pertaining to understanding and forecasting the evolution of atmospheric phenomena which impact North America. More importantly, GOES-16 and GOES-17 will further assist atmospheric scientists to better anticipate how atmospheric features and events evolve prior to even reaching parts of Western North America which is a critical aspect of anticipating major events including (but certainly not limited to) Winter-time extra-tropical cyclones (e.g., Nor'easters). To learn more about this particular story, be sure to click on the brief video briefing attached above. To learn more about other neat observational stories both directly and indirectly related to atmospheric science, be sure to click here! © 2018 Meteorologist Jordan Rabinowitz  DISCUSSION: On Thursday, March 1st, 2018, NASA is scheduled to be launching the GOES-S Satellite by using an Atlas V rocket from Cape Canaveral’s Space Launch Complex 41 in Florida. The launch window for the flight is from 5:02 PM to 7:02 PM EST (22:02 to 0:02 UTC). The GOES-S is the newest member of the fourth generation of the GOES Satellite family which started with GOES-R (GOES-16/GOES-East). The GOES satellites are currently being used for satellite imagery to help meteorologists forecast as well as collect data for research including for thunderstorms and cumulonimbus clouds. Among the instruments on board the satellite includes a lightning mapper and a solar imaging suite which covers certain wavelengths of UV and x-ray radiation from the Sun.
The weather conditions for the launch look preferable as the forecast from the NWS office in Melbourne, Florida calls for near-record high temperatures earlier in the afternoon. In addition, light cloud coverage is expected at the time of the launch but will not interfere. The risk of thunderstorms will be minimal as there is going to be about 100 J/kg of CINH (Convective Inhibition), the energy needed to lift an air parcel up to the lifting condensation level adiabatically. The amount of CINH will be strong enough to likely prevent thunderstorms from forming. In addition, a strong westerly dry flow from Central Florida is expected, which would prevent the formation of sea breeze thunderstorms. The rocket, once launched, will have a boost as there will be westerly winds which would help the rocket pitch its angle to be able to get into orbit. The backup launch date is scheduled for the following day, Friday, March 2nd, 2018. The forecast for the backup date looks to be mostly clear as well with a northerly wind instead of a westerly wind. This is due to a cold front that will be marching across Florida on Thursday and Friday. This backup date is in case there is a technical problem with the Atlas V such as fueling or a malfunction that could not be fixed before the original launch window. The GOES-S will not be operational for a few months until it parks in its first spot in orbit to test its functions. Once this test is completed, the GOES-S (now GOES-17) will move to its new spot as it prepares to replace the GOES-15 as the GOES-West satellite in late 2018. The GOES-15 will become a spare satellite once it gets replaced as the GOES-West for a few years. This will allow for a backup if GOES-17 has a problem with instrumentation or if it needs to be turned off for a few days or weeks. To also learn more about other interesting topics pertaining to meteorological observations, be sure to click here! ©2018 Meteorologist JP Kalb |
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