scholarly journals Constructing a Multifrequency Passive Microwave Hail Retrieval and Climatology in the GPM Domain

2019 ◽  
Vol 58 (9) ◽  
pp. 1889-1904 ◽  
Author(s):  
Sarah D. Bang ◽  
Daniel J. Cecil
Keyword(s):  
United States ◽  
Brightness Temperature ◽  
Microwave Radiometer ◽  
Central Africa ◽  
Tropical Rainfall Measuring Mission ◽  
The United States ◽  
Low Earth Orbit ◽  
Passive Microwave ◽  
Central United States ◽  
Microwave Data

AbstractLarge hail is a primary contributor to damages and loss around the world, in both agriculture and infrastructure. The sensitivity of passive microwave radiometer measurements to scattering by hail led to the development of proxies for severe hail, most of which use brightness temperature thresholds from 37-GHz and higher-frequency microwave channels on board weather satellites in low-Earth orbit. Using 16+ years of data from the Tropical Rainfall Measuring Mission (TRMM; 36°S–36°N), we pair TRMM brightness temperature–derived precipitation features with surface hail reports in the United States to train a hail retrieval on passive microwave data from the 10-, 19-, 37-, and 85-GHz channels based on probability curves fit to the microwave data. We then apply this hail retrieval to features in the Global Precipitation Measurement (GPM) domain (from 69°S to 69°N) to develop a nearly global passive microwave–based climatology of hail. The extended domain of the GPM satellite into higher latitudes requires filtering out features that we believe are over icy and snowy surface regimes. We also normalize brightness temperature depression by tropopause height in an effort to account for differences in storm depth between the tropics and higher latitudes. Our results show the highest hail frequencies in the region of northern Argentina through Paraguay, Uruguay, and southern Brazil; the central United States; and a swath of Africa just south of the Sahel. Smaller hot spots include Pakistan, eastern India, and Bangladesh. A notable difference between these results and many prior satellite-based studies is that central Africa, while still active in our climatology, does not rival the aforementioned regions in retrieved hailstorm frequency.

On the Detection of Hail Using Satellite Passive Microwave Radiometers and Precipitation Radar

2017 ◽  
Vol 56 (10) ◽  
pp. 2693-2709 ◽  
Author(s):  
Xiang Ni ◽  
Chuntao Liu ◽  
Daniel J. Cecil ◽  
Qinghong Zhang
Keyword(s):  
United States ◽  
Brightness Temperature ◽  
Central Africa ◽  
Skill Score ◽  
Radar Reflectivity ◽  
Passive Microwave ◽  
Precipitation Radar ◽  
Microwave Brightness Temperature ◽  
South Central ◽  
Central United States

AbstractIn previous studies, remote sensing properties of hailstorms have been discussed using various spaceborne sensors. Relationships between hail occurrence and strong passive microwave brightness temperature depressions have been established. Using a 16-yr precipitation-feature database derived from the Tropical Rainfall Measuring Mission (TRMM) satellite, the performance of the TRMM Precipitation Radar and TRMM Microwave Imager is further investigated for hail detection. Detection criteria for hail larger than 19 mm are separately developed from Ku-band radar reflectivity and microwave brightness temperature properties of precipitation features that are collocated with surface hail reports over the southeastern and south-central United States. A threshold of 44 dBZ at −22°C is found to have the highest critical success index and Heidke skill score. The threshold of 230 K at 37 GHz yields the best scores among passive microwave properties. Using these two thresholds, global distributions of possible hail events are generated over 65°S–65°N using two years of observations from the Global Precipitation Measurement Core Observatory satellite. Differences in the derived hail geographical distributions are found between radar and passive microwave methods over tropical South America, the “Maritime Continent,” west-central Africa, Argentina, and South Africa. These discrepancies result from different vertical structures of the maximum radar reflectivity profiles over these regions relative to the southeastern and south-central United States, where the thresholds were established. Those differences generally led to overestimates in the tropics from the passive microwave methods, relative to the radar-based methods.

scholarly journals Toward a Global Climatology of Severe Hailstorms as Estimated by Satellite Passive Microwave Imagers

2012 ◽  
Vol 25 (2) ◽  
pp. 687-703 ◽  
Author(s):  
Daniel J. Cecil ◽  
Clay B. Blankenship
Keyword(s):  
United States ◽  
Indian Subcontinent ◽  
Central Africa ◽  
Tropical Rainfall Measuring Mission ◽  
The United States ◽  
Early Morning ◽  
Northern Pakistan ◽  
Diurnal Variability ◽  
Late Night ◽  
Early Afternoon

Abstract An 8-yr climatology of storms producing large hail is estimated from satellite measurements using Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E). This allows a unique, consistent comparison between regions that cannot be consistently compared using ground-based records because of varying data collection standards. Severe hailstorms are indicated most often in a broad region of northern Argentina and southern Paraguay and a smaller region in Bangladesh and eastern India. Numerous hailstorms are also estimated in the central and southeastern United States, northern Pakistan and northwestern India, central and western Africa, and southeastern Africa (and adjacent waters). Fewer hailstorms are estimated for other regions over land and scattered across subtropical oceans. Very few are estimated in the deep tropics other than in Africa. Most continental regions show seasonality with hailstorms peaking in late spring or summer. The South Asian monsoon alters the hailstorm climatology around the Indian subcontinent. About 75% of the hailstorms on the eastern side (around Bangladesh) occur from April through June, generally before monsoon onset. Activity shifts northwest to northern India in late June and July. An arc along the foothills in northern Pakistan becomes particularly active from mid-June through mid-August. The AMSR-E measurements are limited to early afternoon and late night. Tropical Rainfall Measuring Mission (TRMM) measurements are used to investigate diurnal variability in the tropics and subtropics. All of the prominent regions have hailstorm peaks in late afternoon and early evening. The United States and central Africa have the fewest overnight and early morning storms, while subtropical South America and Bangladesh have the most.

Searching and Making Meaning of the COVID-19 Pandemic: Perspectives of African Immigrants in the United States

2021 ◽  
pp. 002216782110224
Author(s):  
Angela U. Ekwonye ◽  
Nina Truong
Keyword(s):  
United States ◽  
Health Care Providers ◽  
Meaning Making ◽  
Democratic Republic Of Congo ◽  
Central Africa ◽  
African Immigrants ◽  
The United States ◽  
Care Providers ◽  
Making Meaning ◽  
The Impact

African immigrants continue to be disproportionately affected by the COVID-19 pandemic. It is unclear how they are searching for and finding meaning in the face of this adversity. This study sought to understand how African immigrants in the United States are searching for and making meaning of the COVID-19 pandemic. We conducted in-depth interviews remotely with 20 immigrants from West Africa (Nigeria and Ghana), East Africa (Somali and Rwanda), and Central Africa (Democratic Republic of Congo). The meaning-making model was used as a framework to understand the processes of coping during a significant, adverse life event. The study found that some participants attempted to reduce the impact of the COVID-19 pandemic on their global meaning by seeking answers as to why the pandemic occurred and creating positive illusions. Some redefined their priorities and reframed the pandemic in a positive light. Participants found meaning in the form of accepting the pandemic as a reality of life, appreciating events previously taken for granted, and making positive changes in their lives. This study’s findings can inform health care providers of the meaning-making processes of African immigrants’ and the need to assist them in their search for meaning.

scholarly journals The Pseudoscorpions of Illinois

1949 ◽  
Vol 24 (1-4) ◽  
pp. 413-500 ◽  
Author(s):  
C. Clayton Hoff
Keyword(s):  
United States ◽  
Natural Habitat ◽  
Habitat Preferences ◽  
The United States ◽  
Accurate Information ◽  
North Central ◽  
Taxonomic Importance ◽  
Central United States ◽  
Identification Of Species ◽  
Made In

Pseudoscorpions are minute animals only a few millimeters long, with the general appearance of diminutive scorpions except that they have no tails. They belong to the large phylum of joint-legged animals, the Arthropoda, and to the class Arachnida. which, in addition to the pseudoscorpions, embraces the spiders, mites, ticks, scorpions, and other related groups. Pseudoscorpions are seclusive in habit, occurring in soil cover and rotten logs, under bark, and in similar places out of doors: one species is found in houses. In their natural habitat, these little brown animals arc difficult to see. especially when they draw in their legs and "play possum." In this position they look like little specks of dirt. Probably because pseudoscorpions are inconspicuous, few collections of the group have been made in the past, and the fauna, at least of North America, and especially of the central and north-central United States, has remained scantily known. The object of this report is twofold, first to present illustrated keys and descriptions for the identification of species in this region, and, secondly, to summarize information regarding the distribution, biology, and habitat preferences of the species. As an aid in use of the keys, a section has been included on morphology, in which the structures now considered of major taxonomic importance are explained. Summarizing the distribution has been especially difficult because many identifications made prior to Chamberlin's work are probably incorrect and should be rechecked before they are cited. Because of this situation there is little accurate information to serve as a guide in foretelling what additional described species may be collected in Illinois. In order to make this report of wide application, the keys have been made to include all the genera known from the central and northeastern portions of the United States and adjacent portions of Canada.

Sea–ice concentration at 1 km resolution in summer from merged visible and microwave radiometer observations

2021 ◽  
Author(s):  
Valentin Ludwig ◽  
Gunnar Spreen
Keyword(s):  
Spatial Resolution ◽  
Microwave Radiometer ◽  
Thermal Infrared ◽  
Passive Microwave ◽  
The Arctic ◽  
Sea Ice Concentration ◽  
Ice Concentration ◽  
Statistical Consistency ◽  
Microwave Data ◽  
Infrared Data

<p>Sea–ice concentration, the surface fraction of ice in a given area, is a key component of the Arctic climate system, governing for example the ocean–atmosphere heat exchange. Satellite–based remote sensing offers the possibility for large–scale monitoring of the sea–ice concentration. Using passive microwave measurements, it is possible to observe the sea–ice concentration all year long, almost independently of cloud coverage. The spatial resolution of these measurements is limited to 5 km and coarser. Data from the visible and thermal infrared spectrum offer finer resolutions of 250 m–1 km, but need clear–sky scenes and, in case of visible data, sunlight. In previous work, we developed and analysed a merged dataset of passive microwave and thermal infrared data, combining AMSR2 and MODIS satellite data at 1 km spatial resolution. It has benefits over passive microwave data in terms of the finer spatial resolution and an enhanced potential for lead detection. At the same time, it outperforms thermal infrared data due to its spatially continuous coverage and the statistical consistency with the extensively evaluated passive microwave data. Due to higher surface temperatures in summer, the thermal–infrared based retrieval is limited to winter and spring months. In this contribution, we present first results of extending the existing dataset to summer by using visible data instead of thermal infrared data. The reflectance contrast between ice and water is used for the sea–ice concentration retrieval and results of merging visible and microwave data at 1 km spatial resolution are presented. Difficulties for both, the microwave and visual, data are surface melt processes during summer, which make sea–ice concentration retrieval more challenging. The merged microwave, infrared and visual dataset opens the possibility for a year–long, spatially continuous sea ice concentration dataset at a spatial resolution of 1 km.</p>

Preventing waterlogging in irrigated agriculture with a multi-satellite sensor approach

2021 ◽  
Author(s):  
Nadja den Besten ◽  
Susan Steele-Dunne ◽  
Richard de Jeu ◽  
Pieter van der Zaag
Keyword(s):  
Water Stress ◽  
Brightness Temperature ◽  
Passive Microwave ◽  
Sensor Data ◽  
Optical Data ◽  
Irrigated Agriculture ◽  
Small Scale ◽  
Drought Event ◽  
Flooding Event ◽  
Microwave Data

<p>Satellite sensors have been used widely to determine water shortages to detect crop stress, with special emphasis on water stress. However, stress resulting from waterlogging has so far received little attention. This is surprising because approximately twenty percent of the global agricultural land suffers from the consequences of waterlogging and secondary soil salinization. While irrigation is expected to increase productivity, excess water can hamper the crop growth and decrease water use efficiency.</p><p>Traditionally, satellite driven water accounting for irrigation assistance uses optical and/or thermal sensors that can detect crop stress. The observed crop stress is often interpreted as water stress, whereby stress resulting from waterlogging cannot be distinguished. We hypothesize that a multi-sensor approach is required to distinguish waterlogging from water shortage, by including microwave observations that can determine the soil moisture status. However, localizing a small-scale phenomena as waterlogging with multi-sensor data with different resolutions is a major challenge.</p><p>In our research we focus on an irrigated sugarcane plantation along the river Incomati in Xinavane, Mozambique. Waterlogging is a common issue in the estate and is threatening productivity. We assess and combine optical and passive microwave data for a large drought (2016) and flooding event (2012) to look at the possibility of downscaling the data for detection of waterlogging. We find that optical indices are able to localize waterlogged areas. Additionally, the built up of the drought event and retreat of the flooding event are clearly visible in the brightness temperature in different frequencies. We demonstrate a procedure to combine brightness temperature with optical data to detect waterlogging at a higher spatial resolution. </p><p>The results show that a combination of optical and passive microwave data can detect regions within the sugarcane plantation of waterlogging. However, high resolution topographic data is required to enhance the detection of waterlogging to finer scales. </p>

Paddlefish Management, Propagation, and Conservation in the 21st Century

2009 ◽  
Keyword(s):  
United States ◽  
The United States ◽  
Fish Production ◽  
Single Source ◽  
Spawning Habitat ◽  
Domestic Consumption ◽  
Central United States ◽  
History Of ◽  
Food Fish ◽  
Aquaculture Production

<em>Abstract</em>.—Paddlefish <em>Polyodon spathula </em>populations in North America have long been exploited commercially for meat and roe; however, the history of paddlefish propagation and culture is more recent. Early efforts to artificially propagate and culture paddlefish were motivated by conservation following the construction of dams and destruction of spawning habitat on major rivers of the central United States. From these beginnings, paddlefish propagation and the species itself have spread from native U.S. waters to other countries, including Russia and China. In the United States, conservation is still an important aspect of paddlefish culture, although sport fishing and aquaculture production have been added to the mix. However, in those countries where paddlefish have been introduced, the motivation has been the perceived potential for producing food for domestic consumption and valuable products for export, including one of the most exotic and expensive food products in today’s world—caviar. The collective efforts of state and federal hatchery personnel in the United States, along with university researchers from the United States and worldwide have resulted in a more complete body of information on paddlefish propagation and culture. Included in this collection are methods for handling broodstock, induced spawning, and nursery stages of production, along with cryopreservation of milt and manipulation of sex ratios in the hatchery to produce a preponderance of female fish. We have assembled this collection here to provide a single source reference and have added information concerning hatchery design, regulations, and the grow-out stages of aquaculture food fish production.

scholarly journals Performance of Landscape Roses Grown with Minimal Input in the North-central, Central, and South-central United States

2017 ◽  
Vol 27 (5) ◽  
pp. 718-730 ◽  
Author(s):  
David C. Zlesak ◽  
Randy Nelson ◽  
Derald Harp ◽  
Barbara Villarreal ◽  
Nick Howell ◽  
...  
Keyword(s):  
United States ◽  
National Level ◽  
The United States ◽  
The South ◽  
Flower Number ◽  
North Central ◽  
The North ◽  
South Central ◽  
Central United States ◽  
Plant Hardiness

Landscape roses (Rosa sp.) are popular flowering shrubs. Consumers are less willing or able to maintain landscape beds than in years past and require plants that are not only attractive, but well-adapted to regional climatic conditions, soil types, and disease and pest pressures. Marketing and distribution of rose cultivars occurs on a national level; therefore, it is difficult for U.S. consumers in the U.S. Department of Agriculture (USDA) Plant Hardiness Zones 3 to 5 to identify well-adapted, cold-hardy cultivars. Identifying suitable cultivars that have strong genetic resistance to pests and disease and that will tolerate temperature extremes without winter protection in the USDA Plant Hardiness Zones 3 to 5 is of tremendous value to consumers and retailers in northern states. Twenty landscape rose cultivars, primarily developed in north-central North America, were evaluated at five locations in the United States (three in the north-central United States, one in the central United States, and one in the south-central United States) using the low-input, multiyear Earth-Kind® methodology. Six roses had ≥75% plant survival at the end of the study and were in the top 50% of performers for overall mean horticultural rating at each of the three north-central U.S. sites: ‘Lena’, ‘Frontenac’, ‘Ole’, ‘Polar Joy’, ‘Sunrise Sunset’, and ‘Sven’. Five of these six roses met the same criteria at the central United States (exception ‘Lena’) and the south-central United States (exception ‘Polar Joy’) sites. Cultivar, rating time, and their interaction were highly significant, and block effects were not significant for horticultural rating for all single-site analyses of variance. Significant positive correlations were found between sites for flower number, flower diameter, and overall horticultural rating. Significant negative correlations were found between flower number and diameter within each site and also between black spot (Diplocarpon rosae) lesion size from a previous study and overall horticultural rating for three of the five sites. Cane survival ratings were not significantly correlated with overall horticultural rating, suggesting some cultivars can experience severe winter cane dieback, yet recover and perform well. Data from this study benefit multiple stakeholders, including nurseries, landscapers, and consumers, with evidence-based regional cultivar recommendations and breeders desiring to identify regionally adapted parents.

scholarly journals Passive Microwave Melt Onset Retrieval Based on a Variable Threshold: Assessment in the Canadian Arctic Archipelago

2019 ◽  
Vol 11 (11) ◽  
pp. 1304 ◽  
Author(s):  
Stephen Marshall ◽  
K. Andrea Scott ◽  
Randall K. Scharien
Keyword(s):  
Brightness Temperature ◽  
Spatial Resolution ◽  
Microwave Radiometer ◽  
Canadian Arctic ◽  
Surface Air Temperature ◽  
Remote Sensing Data ◽  
Passive Microwave ◽  
Canadian Arctic Archipelago ◽  
Variable Threshold ◽  
Resolution Data

The Canadian Arctic Archipelago (CAA) presents unique challenges to the determination of melt onset (MO) using remote sensing data. High spatial resolution data is required to discern melt onset among the islands and narrow waterways of the region. Current passive microwave retrievals use daily averaged 19 GHz and 37 GHz data from the multi-channel microwave radiometer (SMMR) and/or the special sensor microwave/imager (SSM/I). The development of a new passive microwave melt onset method capable of using higher resolution data is desirable. The new passive microwave melt onset method described here, named the Dynamic Threshold Variability Method (DTVM), uses higher resolution data from the 37 GHz vertically-polarized channel from the advanced microwave scanning radiometers (AMSR-E and AMSR-2). The DTVM MO detection methodology differs from previously presented passive microwave Arctic MO methods in that it does not use a fixed threshold of a brightness temperature parameter. Instead, the DTVM determines MO dates based on the distribution of dates corresponding to the exceedance of a range of brightness temperature variability thresholds. The method also uses swath data instead of daily averaged brightness temperatures, which is found to lead to improved melt detection. Two current passive microwave MO methods are compared and evaluated for applicability in the CAA alongside the DTVM. The DTVM provides MO dates at a higher spatial resolution than earlier methods in addition to higher correlation with MO dates from surface air temperature (SAT) reanalyses. It is found that, for some years, MO dates in the CAA exhibit a latitudinal dependence, while in other years the MO dates in the CAA are relatively uniform across the domain.

Knockdown Resistance-Associated Mutations Dominate Populations of the Common Bed Bug (Hemiptera: Cimicidae) Across the South Central United States

2019 ◽  
Vol 56 (6) ◽  
pp. 1678-1683 ◽  
Author(s):  
Jeffrey G Holleman ◽  
Grant A Robison ◽  
Ian J Bellovich ◽  
Warren Booth
Keyword(s):  
United States ◽  
Insecticide Resistance ◽  
The United States ◽  
Knockdown Resistance ◽  
The South ◽  
Α Subunit ◽  
Old World ◽  
Bed Bug ◽  
South Central ◽  
Central United States

Abstract Despite awareness of the mutations conferring insecticide resistance in the bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), within the United States few studies address the distribution and frequency of these. Within the United States, studies have focused on collections made along the East Coast and Midwest, documenting the occurrence of two mutations (V419L and L925I) within the voltage-gated sodium channel α-subunit gene shown to be associated with knockdown resistance (kdr) to pyrethroids. Here, the distribution and frequency of the V419L and L925I site variants is reported from infestations sampled within Oklahoma and its immediately adjacent states. Additionally, the presence of a mutation previously undocumented in the United States (I935F) is noted. While novel in the United States, this mutation has previously been reported in Australian and Old World populations. No infestations were found to harbor wild-type individuals, and hence susceptible, at each of the three sites. Instead, ~21% were found to possess the resistant mutation at the L925I site (haplotype B), ~77% had mutations at both the V419L and L925I sites (haplotype C), and 2% possessed the mutation at the L936F site (haplotype Ab). The high frequency of haplotype C corresponds to previous studies in the United States, and contrasts dramatically with those of the Old World and Australia. The data presented here provide insight into the contemporary occurrence of kdr-associated insecticide resistance in the South Central United States, a region for which data have previously been absent. These data suggest that New World and Old World/Australian infestations are likely to have originated from different origins.

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