Estimating Lightning NOx Production Using NO2 Columns from the TROPOMI Instrument and Flashes from the Geostationary Lightning Mappers

2020 ◽  
Author(s):  
Kenneth Pickering ◽  
Dale Allen ◽  
Eric Bucsela ◽  
Jos van Geffen ◽  
Henk Eskes ◽  
...  
Keyword(s):  
United States ◽  
Case Studies ◽  
The United States ◽  
Data Set ◽  
Case Study Analysis ◽  
Convective Systems ◽  
Convective Clouds ◽  
Deep Convective Clouds ◽  
The One

<p>Nitric oxide (NO) is produced in lightning channels and quickly comes into equilibrium with nitrogen dioxide (NO<sub>2</sub>) in the atmosphere.  The production of NO<sub>x</sub> (NO + NO<sub>2</sub>) leads to subsequent increases in the concentrations of ozone (O<sub>3</sub>) and the hydroxyl radical (OH) and decreases in the concentration of methane (CH<sub>4</sub>), thus impacting the climate system.  Global production of NO<sub>x</sub> from lightning is uncertain by a factor of four.  NO<sub>x</sub> production by lightning will be examined using NO<sub>2</sub> columns from the TROPOspheric Monitoring Instrument (TROPOMI) on board the Copernicus Sentinel-5 Precursor Satellite with an overpass time of approximately 1330 LT and flash rates from the Geostationary Lightning Mapper (GLM) on board the NOAA GOES-16 (75.2° W) and GOES-17 (137.2° W) satellites.  Where there is overlap in coverage of the two GLM instruments, the greater of the two flash counts is used.  Two approaches have been undertaken for this analysis:  a series of case studies of storm systems over the United States, and a gridded analysis over the entire contiguous United States, Central America, northern South America, and surrounding oceans.  A modified Copernicus Sentinel 5P TROPOMI NO<sub>2</sub> data set is used here for the case-study analysis to improve data coverage over deep convective clouds.  In both approaches, only TROPOMI pixels with cloud fraction > 0.95 and cloud pressure < 500 hPa are used.  The stratospheric column is removed from the total slant column, and the result is divided by air mass factors appropriate for deep convective clouds containing lightning NO<sub>x</sub> (LNO<sub>x</sub>).  Case studies have been selected from deep convective systems over and near the United States during the warm seasons of 2018 and 2019.  For each of these systems, NO<sub>x</sub> production per flash is determined by multiplying a TROPOMI-based estimate of the mean tropospheric column of LNO<sub>x</sub> over each system by the storm area and then dividing by a GLM-based estimate of the flashes that contribute to the column.  In the large temporal and spatial scale analysis, the TROPOMI data are aggregated on a 0.5 x 0.5 degree grid and converted to moles LNO<sub>x</sub>*.  GLM flash counts during the one-hour period before TROPOMI overpass are similarly binned. A tropospheric background of LNO<sub>x</sub>* is estimated from grid cells without lightning and subtracted from LNO<sub>x</sub>* in cells with lightning to yield an estimate of freshly produced lightning NO<sub>x</sub>, designated LNO<sub>x</sub>.  Results of the two approaches are compared and discussed with respect to previous LNO<sub>x</sub> per flash estimates.</p><p> </p>

Pre-Attack Warning Behaviors of 20 Adolescent School Shooters: A Case Study Analysis

2021 ◽  
pp. 001112872199933
Author(s):  
Meagan N. Abel ◽  
Steven Chermak ◽  
Joshua D. Freilich
Keyword(s):  
United States ◽  
Case Studies ◽  
The United States ◽  
Study Analysis ◽  
Case Study Analysis ◽  
The Us ◽  
Online Forms ◽  
School Shooters ◽  
K 12

This study examines the pre-attack warning behaviors of adolescent school shooters in the US. We conducted 20 case studies of adolescent school shooters in the United States that committed non-fatal or fatal shootings on K-12 school grounds between 1999 and 2016. We investigate whether the school shooters displayed warning behaviors before the attack, who in the perpetrator’s life was aware of these warning behaviors, and what if any actions were taken in response. Given the emergence of online forms of communication, we also investigate how adolescent school shooters may variably communicate warning behaviors in online and offline contexts.

Is Distance to Drop Box an Appropriate Proxy for Drop Box Treatment? A Case Study of Washington State

2021 ◽  
pp. 1532673X2110221
Author(s):  
Loren Collingwood ◽  
Benjamin Gonzalez O’Brien
Keyword(s):  
United States ◽  
Voter Turnout ◽  
The United States ◽  
Washington State ◽  
Individual Level ◽  
Primary 52 ◽  
The One ◽  
Vote By Mail

In the United States, drop box mail-in voting has increased, particularly in the all vote by mail (VBM) states of Washington, Colorado, Utah, and Oregon. To assess if drop boxes improve voter turnout, research proxies box treatment by voters’ residence distance to nearest drop box. However, no research has tested the assumption that voters use drop boxes nearest their residence more so than they do other drop boxes. Using individual-level voter data from a 2020 Washington State election, we show that voters are more likely to use the nearest drop box to their residence relative to other drop boxes. In Washington’s 2020 August primary, 52% of drop box voters in our data used their nearest drop box. Moreover, those who either (1) vote by mail, or (2) used a different drop box from the one closest to their residence live further away from their closest drop box. Implications are discussed.

scholarly journals Learning from Past Policy: Assessing United States Foreign Policy over Indonesia in Resolving the 1999 East Timor Crisis

2021 ◽  
Vol 23 (1) ◽  
pp. 1
Author(s):  
Sigit S. Nugroho
Keyword(s):  
United States ◽  
Foreign Policy ◽  
Low Cost ◽  
The United States ◽  
East Timor ◽  
United States Foreign Policy ◽  
Case Study Analysis ◽  
High Degree ◽  
The U.S

Assessing the output of past foreign policy is instrumental for any country to learn policy-relevant insights, to appreciate its experience, and to improve its future conduct. To glean such insights, this article borrows Baldwin’s framework in assessing the success and failure in foreign policy. Using a case study analysis, it assesses the United States’ (U.S.) influence attempt towards Indonesia to resolve the 1999 East Timor humanitarian crisis. President Clinton’s decision to undergo an influence attempt primarily aimed to change Indonesia’s policy while gaining support from U.S. allies in the process. The article finds that Clinton’s decision was a highly successful attempt. This finding is based on several factors: (1) the attempt effectively attained the intended primary and secondary goals at a considerably high degree; (2) it was conducted at a considerably low cost for the U.S.; (3) it inflicted a high cost towards Indonesia; (4) the increase in Clinton’s stake strengthened the U.S. resolve to pursue the influence attempt; and (5) Clinton had successfully overcome the difficult undertaking as Indonesia possessed higher stake over East Timor. These findings provide some lessons for both U.S. and Indonesian foreign policymakers to chart future relations for the two nations.

The Value of Wind Profiler Data in U.S. Weather Forecasting

2004 ◽  
Vol 85 (12) ◽  
pp. 1871-1886 ◽  
Author(s):  
Stanley G. Benjamin ◽  
Barry E. Schwartz ◽  
Edward J. Szoke ◽  
Steven E. Koch
Keyword(s):  
United States ◽  
Case Studies ◽  
Short Range ◽  
Weather Forecasting ◽  
The United States ◽  
Test Period ◽  
Data Sources ◽  
Wind Profiler ◽  
Profiler Data

An assessment of the value of data from the NOAA Profiler Network (NPN) on weather forecasting is presented. A series of experiments was conducted using the Rapid Update Cycle (RUC) model/assimilation system in which various data sources were denied in order to assess the relative importance of the profiler data for short-range wind forecasts. Average verification statistics from a 13-day cold-season test period indicate that the profiler data have a positive impact on short-range (3–12 h) forecasts over the RUC domain containing the lower 48 United States, which are strongest at the 3-h projection over a central U.S. subdomain that includes most of the profiler sites, as well as downwind of the profiler observations over the eastern United States. Overall, profiler data reduce wind forecast errors at all levels from 850 to 150 hPa, especially below 300 hPa where there are relatively few automated aircraft observations. At night when fewer commercial aircraft are flying, profiler data also contribute strongly to more accurate 3-h forecasts, including near-tropopause maximum wind levels. For the test period, the profiler data contributed up to 20%–30% (at 700 hPa) of the overall reduction of 3-h wind forecast error by all data sources combined. Inclusion of wind profiler data also reduced 3-h errors for height, relative humidity, and temperature by 5%-15%, averaged over different vertical levels. Time series and statistics from large-error events demonstrate that the impact of profiler data may be much larger in peak error situations. Three data assimilation case studies from cold and warm seasons are presented that illustrate the value of the profiler observations for improving weather forecasts. The first case study indicates that inclusion of profiler data in the RUC model runs for the 3 May 1999 Oklahoma tornado outbreak improved model guidance of convective available potential energy (CAPE), 300-hPa wind, and precipitation in southwestern Oklahoma at the onset of the event. In the second case study, inclusion of profiler data led to better RUC precipitation forecasts associated with a severe snow and ice storm that occurred over the central plains of the United States in February 2001. A third case study describes the effect of profiler data for a tornado event in Oklahoma on 8 May 2003. Summaries of National Weather Service (NWS) forecaster use of profiler data in daily operations, although subjective, support the results from these case studies and the statistical forecast model impact study in the broad sense that profiler data contribute significantly to improved short-range forecasts over the central United States where these observations currently exist.

Case Study Analysis of Pedestrian and Bicycle Data Collection in U.S. Communities

2005 ◽  
Vol 1939 (1) ◽  
pp. 77-90 ◽  
Author(s):  
Robert J. Schneider ◽  
Robert S. Patten ◽  
Jennifer L. Toole
Keyword(s):  
United States ◽  
New York ◽  
Data Collection ◽  
The United States ◽  
Case Study Analysis ◽  
Study Approach ◽  
Data Collection Strategy ◽  
Facility Construction ◽  
Collection Methods

Federal funding for pedestrian and bicycle transportation has increased over the past 15 years, with a resulting increase in shared-use pathways, paved shoulders, bicycle lanes, and sidewalks in many parts of the United States. This has caused communities to ask questions: Where is pedestrian and bicycle activity taking place? What effect does facility construction have on levels of bicycling and walking? What are the characteristics of nonmotorized transportation users? How many miles of pedestrian and bicycle facilities are available? Where are existing facilities located? This paper provides a summary of recent research that was sponsored by FHWA and the Pedestrian and Bicycle Information Center to review and evaluate bicycle and pedestrian data collection methods throughout the United States. It uses a case study approach to evaluate pedestrian and bicycle data collection in 29 different agencies throughout the country in communities ranging in size from 6,000 residents (Sandpoint, Idaho) to 8 million residents (New York City). These case studies are analyzed in the following data collection categories: manual counts, automated counts, surveys targeting nonmotorized transportation users, surveys sampling a general population, inventories, and spatial analyses. The results provide information about the methods and the optimum timing for pedestrian and bicycle data collection; emerging technologies that can be used to gather and analyze data; the benefits, limitations, and costs of different data collection techniques; and implications for a national data collection strategy.

Troubling solutions through anthropological fieldwork: Mediation research in Ghana, Australia, and the United States

2021 ◽  
Vol 20 (6) ◽  
pp. 1441-1460
Author(s):  
Alexandra Crampton
Keyword(s):  
United States ◽  
Social Work ◽  
Expert Knowledge ◽  
The United States ◽  
Research Field ◽  
Court Cases ◽  
Research Goal ◽  
Anthropological Fieldwork ◽  
The One

Social workers and anthropologists encounter different representations of mediation as a professional practice: On the one hand, Social Work is grounded in mediation as expert knowledge that helps others to resolve interpersonal disputes. For example, mediation as Alternative Dispute Resolution (ADR) can enable court cases to resolve without formal trials. On the other hand, Anthropology is grounded in mediation as a research field site and by past intervention experience of anthropologists. As mediation professionalized and became mandated across public institutions, anthropologists became strong ADR critics. Academic debate between mediation proponents and critics ended as critics abandoned research in the 1990s and 2000s. My initial research goal was to pick up from past empirical study. Research was conducted in Australia, Ghana, and the United States in two areas of mediation practice; resolving parenting disputes between adults who are separating or not married, and “elder mediation” cases involving older adults. Initial findings reified past debate through data that supported proponents and critics. Further insight was gained through return to fieldwork using an expanded, ethnographic case study design. This article provides a journey through a seemingly intractable divide that was ultimately resolved through prolonged time in fieldwork focused on understanding client perspectives. I show how social work and anthropology scholars of professional mediation have been positioned on opposite sides of an expert knowledge/fieldwork research boundary. This boundary can be made productive through open exchange about mediation as a practice that evolves through an interplay of expert knowledge, intervention practice, and client engagement.

scholarly journals The United States, China and the WTO after Coronavirus

2020 ◽  
Author(s):  
Doug Stokes ◽  
Martin Williamson
Keyword(s):  
United States ◽  
World Trade Organisation ◽  
The United States ◽  
Structural Power ◽  
Case Study Analysis ◽  
Bretton Woods ◽  
Archival Material ◽  
Monetary Regime ◽  
The World

Abstract A hegemon can destroy its international regimes, but what happens when it does not possess the capacity to reconstitute a regime to its liking? Drawing on structural power theory, our article examines President Nixon’s historic attacks on the Bretton Woods international monetary regime to help illuminate President Trump’s attacks on the World Trade Organisation (WTO). In both cases regime destruction was driven to a large extent by a desire to contain rivals: Europe for Nixon, China for Trump. Drawing on original archival material, our case study analysis shows that while the United States possessed sufficient negative structural power to derail Bretton Woods, it lacked sufficient positive structural power to create the new monetary structure Nixon wanted. Trump faces a similar dilemma: he can block the WTO regime, but cannot necessarily replace it with one to the United States’ liking. China is too powerful and possesses too much structural power of its own to give up its WTO privileges without a fight. After the Coronavirus pandemic, it is unlikely that China can prevent the United States from wrecking the WTO trade regime, but very likely it can block US attempts to create a successor regime tailored exclusively to US requirements.

scholarly journals Outsiders and the Amateur Legislature: A Case Study of Legislative Politics

1986 ◽  
Vol 6 ◽  
pp. 22-34
Author(s):  
Arthur English ◽  
John J. Carroll
Keyword(s):  
United States ◽  
Rhode Island ◽  
The United States ◽  
The Other ◽  
Legislative Politics ◽  
United States Congress ◽  
Part Time ◽  
The One ◽  
Legislative Institutions

Political scientists have concentrated their analyses on the United States Congress and legislatures in the larger states, while developing a literature rich in insight on legislative institutions. But this literature has often overlooked that most typical, albeit declining, legislative phenomena, the amateur or citizens legislatures which are found in the smaller and more rural states. The defining difference between these two types of legislative institutions, i.e., between the "professionalized” Congress, California legislature, and the amateur Rhode Island or Arkansas General Assemblies, is that in the one legislators "legislate" for a living while in the other members serve part-time and draw their principal paychecks elsewhere.

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