Rajul E. Pandya

The Influence of Convectively Generated Thermal Forcing on the Mesoscale Circulation around Squall Lines

Abstract The dynamical processes that determine the kinematic and thermodynamic structure of the mesoscale region around 2D squall lines are examined using a series of numerical simulations. The features that develop in a realistic reference simulation of a squall line with trailing stratiform precipitation are compared to the features generated by a steady thermal forcing in a “dry” simulation with no microphysical parameterization. The thermal forcing in the dry simulation is a scaled and smoothed time average of the latent heat released and absorbed in and near the leading convective line in the reference simulation. The mesoscale circulation in the dry simulation resembles the mesoscale circulation in the reference simulation and around real squall lines; it includes an ascending front-to-rear flow, a midlevel rear inflow, a mesoscale up- and downdraft, an upper-level rear-to-front flow ahead of the thermal forcing, and an upper-level cold anomaly to the rear of the thermal forcing. It is also shown t...

Linear Stratospheric Gravity Waves above Convective Thermal Forcing

Abstract The spectra of linear gravity waves generated by a time-varying tropospheric thermal forcing representing organized convection are compared to the spectra of stratospheric gravity waves generated by organized convection in a fully nonlinear two-dimensional squall line simulation. The resemblance between the spectra in the two simulations suggests that stratospheric gravity waves above convection can be understood primarily in terms of the linear response to a time- and space-dependent thermal forcing. In particular, the linear response to thermal forcing accounts for the correlation between the dominant vertical wavelength of the stratospheric waves and the depth of the tropospheric convection as well as the the fact that the dominant frequency of the stratospheric waves is the same as the frequency of oscillation of the main convective updraft.

A framework for engaging diverse communities in citizen science in the US

Citizen science is a powerful tool for connecting people to science, but in the US, such initiatives have not connected as well to groups that have been historically underrepresented in science. Research suggests that while several factors contribute to this lack of diverse participation in citizen science, the critical hurdle may be an absence of alignment between community priorities and research objectives. Here, I discuss a participatory framework for designing citizen-science programs that align with community priorities.

The Influence of Convective Thermal Forcing on the Three-Dimensional Circulation around Squall Lines

Abstract Midlatitude squall lines are typically trailed by a large region of stratiform cloudiness and precipitation with significant mesoscale flow features, including an ascending front to rear flow; a descending rear inflow jet; line-end vortices; and, at later times, mesoscale convective vortices. The present study suggests that the mesoscale circulation in the trailing stratiform region is primarily determined by the time-mean pattern of heating and cooling in the leading convective line. Analysis of the line-normal circulation shows that it develops as thermally generated gravity waves spread away from the leading line. Midlevel line-end vortices are the result of diabatically driven tilting of horizontal vorticity generated by the time-mean thermal forcing. In the presence of the Coriolis force, a symmetric thermal forcing generates an asymmetric stratiform circulation and a pattern of vertical displacement that resembles the comma-shaped stratiform anvil observed in real systems; this suggests tha...

Climate change and indigenous peoples in the United States: Impacts, experiences and actions

Federally-recognized tribes must adapt to many ecological challenges arising from climate change, from the effects of glacier retreat on the habitats of culturally significant species to how sea leave rise forces human communities to relocate. The governmental and social institutions supporting tribes in adapting to climate change are often constrained by political obstructions, raising concerns about justice. Beyond typical uses of justice, which call attention to violations of formal rights or to considerations about the degree to which some populations may have caused anthropogenic climate change, a justice framework should guide how leaders, scientists and professionals of all heritages andwhoworkwith or for federally-recognized tribes understand what actions are morally essential for supporting tribes’ adaptation efforts. This paper motivates a shift to a forward-looking framework of justice. The framework situates justice within the systems of responsibilities that matter to tribes and many others, which range from webs of inter-species relationships to government-to-government partnerships. Justice is achieved when these systems of responsibilities operate in ways that support the continued flourishing of tribal communities.

Knowledge, Attitudes, and Practices Related to Meningitis in Northern Ghana

Meningitis has a significant impact in the Sahel, but the mechanisms for transmission and factors determining a persons vulnerability are not well understood. Our survey examined the knowledge, attitudes, and practices of people in a meningitis-endemic area in the Upper East region of northern Ghana to identify social, economic, and behavioral factors that may contribute to disease transmission and possible interventions that might improve health outcomes. Key results suggest potential interventions in response to the risk posed by migration, especially seasonal migration, a lack of knowledge about early symptoms causing delayed treatment, and a need for further education about the protective benefits of vaccination.

Meningitis and Climate: From Science to Practice

Meningococcal meningitis is a climate sensitive infectious disease. The regional extent of the Meningitis Belt in Africa, where the majority of epidemics occur, was originally defined by Lapeysonnie in the 1960s. A combination of climatic and environmental conditions and biological and social factors have been associated to the spatial and temporal patterns of epidemics observed since the disease first emerged in West Africa over a century ago. However, there is still a lack of knowledge and data that would allow disentangling the relative effects of the diverse risk factors upon epidemics. The Meningitis Environmental Risk Information Technologies Initiative (MERIT), a collaborative research-to-practice consortium, seeks to inform national and regional prevention and control strategies across the African Meningitis Belt through the provision of new data and tools that better determine risk factors. In particular MERIT seeks to consolidate a body of knowledge that provides evidence of the contribution of climatic and environmental factors to seasonal and year-to-year variations in meningococcal meningitis incidence at both district and national scales. Here we review recent research and practice seeking to provide useful information for the epidemic response strategy of National Ministries of Health in the Meningitis Belt of Africa. In particular the research and derived tools described in this paper have focused at “getting science into policy and practice” by engaging with practitioner communities under the umbrella of MERIT to ensure the relevance of their work to operational decision-making. We limit our focus to that of reactive vaccination for meningococcal meningitis. Important but external to our discussion is the development and implementation of the new conjugate vaccine, which specifically targets meningococcus A.

Using Weather Forecasts to Help Manage Meningitis in the West African Sahel

AbstractUnderstanding and acting on the link between weather and meningitis in the Sahel could help improve vaccine distribution and save lives. People living there know that meningitis epidemics occur in the dry season and end after the start of the rainy season. Integrating and analyzing newly available epidemiological and meteorological data quantified this relationship, showing that that the risk of meningitis epidemics climbed from a background level of 2% to a maximum risk of 25% during the dry season. These data also suggested that, of all meteorological variables, relative humidity has the strongest correlation to cases of meningitis.Weather acts alongside a complex set of environmental, social, and economic drivers, and a complementary investigation of local and regional knowledge, attitudes, and practices suggested several additional interventions to manage meningitis. These include improved awareness of early meningitis symptoms and vaccinations for farmworkers who migrate seasonally. An econom...

11TH AMS Education Symposium

The 11th American Meteorological Society (AMS) Education Symposium was held from 13 to 15 January 2002 in Orlando, Florida, as part of the 82nd Annual Meeting of the AMS. The theme of the symposium was “creating opportunities in educational outreach in the atmospheric and related sciences.” Drawing from traditional strengths in meteorology and numerous national recommendations, the presentations and posters of the symposium highlighted three opportunities for reform. These opportunities build on partnerships between diverse educational stakeholders, efforts to make science education more like scientific practice, and strategies that place the atmospheric sciences within a larger, multidisciplinary context that includes oceanography, hydrology, and earth-system science.

AMS MEMBERSHIP SURVEY RESULTS: An Overview and Longitudinal Analysis of the Demographics of the AMS

Abstract The 2005 membership survey is the fifth in a series of surveys that has monitored the composition of the AMS since 1975. The responses of the 2005 survey reveal several interesting changes in the educational level, employment characteristics, and personal status of Society members. The proportion of members with Ph.D. degrees has increased with time to 46% of the regular (nonstudent) and retired members in 2005. Universities/colleges, the federal government, and radio/TV remain the three most important employers of AMS members, although their relative importance has changed with time, with universities/colleges now employing more members than the federal government. Most AMS members continue to report that they became interested in the atmospheric sciences in either elementary school or as undergraduates, although the importance of early (K–6) experiences has increased with time. The age distribution of AMS members in 2005 suggests that the gradual aging of the AMS membership reported earlier (ba...