53 research outputs found
Using Self-Organizing Maps to Investigate Extreme Climate Events: An Application to Wintertime Precipitation in the Balkans
The International Society for Burns Injuries (ISBI) has published guidelines for the management of multiple or mass burns casualties, and recommends that 'each country has or should have a disaster planning system that addresses its own particular needs.' The need for a national burns disaster plan integrated with national and provincial disaster planning was discussed at the South African Burns Society Congress in 2009, but there was no real involvement in the disaster planning prior to the 2010 World Cup; the country would have been poorly prepared had there been a burns disaster during the event. This article identifies some of the lessons learnt and strategies derived from major burns disasters and burns disaster planning from other regions. Members of the South African Burns Society are undertaking an audit of burns care in South Africa to investigate the feasibility of a national burns disaster plan. This audit (which is still under way) also aims to identify weaknesses of burns care in South Africa and implement improvements where necessary
Relative Performance of Empirical Predictors of Daily Precipitation
The urgent need for realistic regional climate change scenarios has led to a plethora of empirical downscaling techniques. In many cases widely differing predictors are used, making comparative evaluation difficult. Additionally, it is not clear that the chosen predictors are always the most important. These limitations and the lack of physics in empirical downscaling highlight the need for a systematic assessment of the performance of physically meaningful predictors and their relevance in surface climate parameters. Accordingly, the objectives of this study are twofold: To examine the skill and errors of 29 individual atmospheric predictors of area-averaged daily precipitation in 15 locations that encompass a wide variety of climate regimes, and to determine the best combination of these to empirically model daily precipitation during the winter and summer seasons. The atmospheric predictors utilized in this study are from the National Center for Environmental Prediction (NCEP) Reanalysis. This work is not concerned with evaluating a particular downscaling methodology, but rather with evaluating the relative skill of physically meaningful predictors that are able to capture different sources of variation. The results indicate that humidity and geopotential heights at mid-tropospheric levels are the two most relevant controls of daily precipitation in all the locations and seasons analyzed. A less ubiquitous role is played by the tropospheric thickness, and the surface meridional and 850-hPa wind components, which appear to be regionally and seasonally dependent. Poor skill is found in the near-equatorial regions and in the Tropics where convective processes dominate and, possibly, where the reanalysis data sets utilized are most deficient. The warm season hemisphere is characterized by the largest errors, likely also due to the enhanced role of convection and sub-grid scale processes during this season. Discrepancies between the performance of the downscaling at grid cell (2o lat x 2.5o lon) and local scales further indicate the sensitivity to the spatial resolution of the predictors
Robust late twenty-first century shift in the regional monsoons in RegCM-CORDEX simulations
AbstractWe use an unprecedented ensemble of regional climate model (RCM) projections over seven regional CORDEX domains to provide, for the first time, an RCM-based global view of monsoon changes at various levels of increased greenhouse gas (GHG) forcing. All regional simulations are conducted using RegCM4 at a 25 km horizontal grid spacing using lateral and lower boundary forcing from three General Circulation Models (GCMs), which are part of the fifth phase of the Coupled Model Inter-comparison Project (CMIP5). Each simulation covers the period from 1970 through 2100 under two Representative Concentration Pathways (RCP2.6 and RCP8.5). Regional climate simulations exhibit high fidelity in capturing key characteristics of precipitation and atmospheric dynamics across monsoon regions in the historical period. In the future period, regional monsoons exhibit a spatially robust delay in the monsoon onset, an increase in seasonality, and a reduction in the rainy season length at higher levels of radiative forcing. All regions with substantial delays in the monsoon onset exhibit a decrease in pre-monsoon precipitation, indicating a strong connection between pre-monsoon drying and a shift in the monsoon onset. The weakening of latent heat driven atmospheric warming during the pre-monsoon period delays the overturning of atmospheric subsidence in the monsoon regions, which defers their transitioning into deep convective states. Monsoon changes under the RCP2.6 scenario are mostly within the baseline variability
Projected changes in temperature and precipitation over the United States, Central America and the Caribbean in CMIP6 GCMs
The Coupled Model Intercomparison Project Phase 6 (CMIP6) dataset is used to examine projected changes in temperature and precipitation over the United States (U.S.), Central America and the Caribbean. The changes are computed using
an ensemble of 31 models for three future time slices (2021–2040, 2041–2060, and 2080–2099) relative to the reference
period (1995–2014) under three Shared Socioeconomic Pathways (SSPs; SSP1-2.6, SSP2-4.5, and SSP5-8.5). The CMIP6
ensemble reproduces the observed annual cycle and distribution of mean annual temperature and precipitation with biases
between − 0.93 and 1.27 °C and − 37.90 to 58.45%, respectively, for most of the region. However, modeled precipitation is
too large over the western and Midwestern U.S. during winter and spring and over the North American monsoon region in
summer, while too small over southern Central America. Temperature is projected to increase over the entire domain under
all three SSPs, by as much as 6 °C under SSP5-8.5, and with more pronounced increases in the northern latitudes over the
regions that receive snow in the present climate. Annual precipitation projections for the end of the twenty-frst century
have more uncertainty, as expected, and exhibit a meridional dipole-like pattern, with precipitation increasing by 10–30%
over much of the U.S. and decreasing by 10–40% over Central America and the Caribbean, especially over the monsoon
region. Seasonally, precipitation over the eastern and central subregions is projected to increase during winter and spring and
decrease during summer and autumn. Over the monsoon region and Central America, precipitation is projected to decrease
in all seasons except autumn. The analysis was repeated on a subset of 9 models with the best performance in the reference
period; however, no signifcant diference was found, suggesting that model bias is not strongly infuencing the projections.Universidad de Costa Rica/[805-B9-454]/UCR/Costa RicaNational Science Foundation/[AGS-1849654]/NSF/Estados UnidosNational Science Foundation/[AGS-1623912]/NSF/Estados UnidosDepartment of Energy/[2316‐T849‐08]/DOE/Estados UnidosNational Oceanic and Atmospheric Administration/[2316‐T849‐08]/NOAA/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones Geofísicas (CIGEFI)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR
Putting into action the REGCM4.6 regional climate model for the study of climate change, variability and modeling over Central America and Mexico
What: International experts and attendees from several countries of Central America, Mexico, the Caribbean (CAM), and South America (SA) met to discuss regional issues on climate variability and climate change to learn the use of the non-hydrostatic version of the International Center for Theoretical Physics (ICTP) RegCM4.6 model, and to establish a regional modeling scientific community for understanding the physics of climate processes and the generation of regional climate change scenarios.
When: 14-18 November 2016.
Where: Center for Geophysical Research (CIGEFI in Spanish) and School of Physics, University of Costa Rica (UCR), San José, Costa Rica.Ministerio de Ciencia, Tecnología y Telecomunicaciones/[FI-0015-16]/MICITT/Costa RicaUniversidad de Costa Rica/[805-B0-065]/UCR/Costa RicaUniversidad de Costa Rica/[805-A8-606]/UCR/Costa RicaUniversidad de Costa Rica/[805-B0-130]/UCR/Costa RicaUniversidad de Costa Rica/[805-A9-224]/UCR/Costa RicaUniversidad de Costa Rica/[805-A7-002]/UCR/Costa RicaUniversidad de Costa Rica/[805-B0-402]/UCR/Costa RicaUniversidad de Costa Rica/[805-B3-600]/UCR/Costa RicaUniversidad de Costa Rica/[805-B4-227]/UCR/Costa RicaUniversidad de Costa Rica/[805-B5-296]/UCR/Costa RicaUniversidad de Costa Rica/[808-A9-180]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones Geofísicas (CIGEFI
Global exposure of population and land‐use to meteorological droughts under different warming levels and SSPs: a CORDEX‐based study
Global warming is likely to cause a progressive drought increase in some regions, but how population and natural resources will be affected is still underexplored. This study focuses on global population, forests, croplands and pastures exposure to meteorological drought hazard in the 21st century, expressed as frequency and severity of drought events. As input, we use a large ensemble of climate simulations from the Coordinated Regional Climate Downscaling Experiment (CORDEX), population projections from the NASA-SEDAC dataset and land-use projections from the Land-Use Harmonization 2 project for 1981–2100. The exposure to drought hazard is presented for five Shared Socioeconomic Pathways (SSP1-SSP5) at four Global Warming Levels (GWLs: 1.5°C to 4°C). Results show that considering only Standardized Precipitation Index (SPI; based on precipitation), the SSP3 at GWL4 projects the largest fraction of the global population (14%) to experience an increase in drought frequency and severity (versus 1981–2010), with this value increasing to 60% if temperature is considered (indirectly included in the Standardized Precipitation-Evapotranspiration Index, SPEI). With SPEI, considering the highest GWL for each SSP, 8 (for SSP2, SSP4, SSP5) and 11 (SSP3) billion people, that is, more than 90%, will be affected by at least one unprecedented drought. For SSP5 at GWL4, approximately 2 × 10 km of forests and croplands (respectively, 6% and 11%) and 1.5 × 10 km of pastures (19%) will be exposed to increased drought frequency and severity according to SPI, but for SPEI this extent will rise to 17 × 10 km of forests (49%), 6 × 10 km of pastures (78%) and 12 × 10 km of croplands (67%), being mid-latitudes the most affected. The projected likely increase of drought frequency and severity significantly increases population and land-use exposure to drought, even at low GWLs, thus extensive mitigation and adaptation efforts are needed to avoid the most severe impacts of climate change
Challenges for climate change adaptation in Latin America and the Caribbean region
The limited success of international efforts to reduce global warming at levels established in the Paris Agreement, and the increasing frequency and strength of climate impacts, highlight the urgent need of adaptation, particularly in developing countries. Unfortunately, current levels of adaptation initiatives are not enough to counteract the observed impacts and projected risks from climate change in Latin America and the Caribbean (LAC). In this paper, we review and highlight relevant issues that have limited the capacity to transform climate knowledge and parties’ ambitions into action in the region. Current vulnerabilities and climatic impact-drivers in LAC are diverse, complex, and region-specific and their effects are expected to be exacerbated by climate change. However, the advancement of regional and domestic climate agendas has been hindered by scientific gaps, political support, institutional capacity, and financial, technical, human, and economic limitations that are common to many LAC countries. Transforming climate data into multidimensional metrics with useful thresholds for different sectors and understanding their contribution for feasible adaptation strategies are delayed by regional and local conundrums such as lack of inclusive governance, data availability, equity, justice, and transboundary issues. We discuss ways to move forward to develop local and regional climate resilient development actions and a more sustainable future in LAC. The climate science community in LAC needs to strengthen its local, national, and international connections and with decision/policymakers and society to establish a three-way engagement by proposing suitable adaptation actions and international negotiations to reduce the risks and vulnerability associated with climate extremes, climate variability and climate change in the region. The discussions and insights presented in this work could be extrapolated to other countries in the Global South
The influence of the southern oscillation on the winter climate of Nuevo Leon state, Mexico
El propósito de este trabajo es estudiar la influencia de la Oscilación del Sur sabre el clima invernal (noviembre/abril) del Estado de Nuevo León, México. El estudio se fundamenta a través de un análisis de correlacion de temperatura media, precipitación, datos de radio-sondeo y un ídice de Ia Oscilación del Sur, definido como bajo cuando la presion a nivel del mares anormalmente baja/alta en Tahiti/Darwin. Los resultados muestran un aumento significativo de precipitacion y una tendencia hacia temperaruras menores en casi todo el estado, especialmente a barlovento de la Sierra Madre Oriental durante el invierno de los eventos de El Niño o fase baja de la Oscilación del Sur. Asimismo, se obtuvieron anomalías negativas de alturas geopotenciales a 850mb en el Golfo de México durante la misma fase. Estos resultados se asocian con una influencia conjugada de los Nortes sabre la región costera del golfo norte y de los fuertes vientos del oeste que acompafian a Ia corriente de chorro subtropical durante tales eventos. Los resultados del estudio indican que la Oscilacion del Sur tiene un impacto sobre el clima invernal de Nuevo León con influencias modulantes de caracter regional como son los Nones y Ia Sierra Madre Oriental.
doi: https://doi.org/10.22201/igeof.00167169p.1994.33.2.47
Large-Scale Circulation Anomalies Conducive to Extreme Precipitation Events and Derivation of Daily Rainfall in Northeastern Mexico and Southeastern Texas
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