A USCLIVAR Project to Assess and Compare the Responses of Global Climate Models to Drought-Related SST Forcing Patterns: Overview and Results

The USCLI VAR working group on drought recently initiated a series of global climate model simulations forced with idealized SST anomaly patterns, designed to address a number of uncertainties regarding the impact of SST forcing and the role of land-atmosphere feedbacks on regional drought. Specific questions that the runs are designed to address include: What are the mechanisms that maintain drought across the seasonal cycle and from one year to the next? What is the role of the leading patterns of SST variability, and what are the physical mechanisms linking the remote SST forcing to regional drought, including the role of land-atmosphere coupling? The runs were carried out with five different atmospheric general circulation models (AGCM5), and one coupled atmosphere-ocean model in which the model was continuously nudged to the imposed SST forcing. This paper provides an overview of the experiments and some initial results focusing on the responses to the leading patterns of annual mean SST variability consisting of a Pacific El Nino/Southern Oscillation (ENSO)-like pattern, a pattern that resembles the Atlantic Multi-decadal Oscillation (AMO), and a global trend pattern. One of the key findings is that all the AGCMs produce broadly similar (though different in detail) precipitation responses to the Pacific forcing pattern, with a cold Pacific leading to reduced precipitation and a warm Pacific leading to enhanced precipitation over most of the United States. While the response to the Atlantic pattern is less robust, there is general agreement among the models that the largest precipitation response over the U.S. tends to occur when the two oceans have anomalies of opposite sign. That is, a cold Pacific and warm Atlantic tend to produce the largest precipitation reductions, whereas a warm Pacific and cold Atlantic tend to produce the greatest precipitation enhancements. Further analysis of the response over the U.S. to the Pacific forcing highlights a number of noteworthy and to some extent unexpected results. These include a seasonal dependence of the precipitation response that is characterized by signal-to-noise ratios that peak in spring, and surface temperature signal-to-noise ratios that are both lower and show less agreement among the models than those found for the precipitation response. Another interesting result concerns what appears to be a substantially different character in the surface temperature response over the U.S. to the Pacific forcing by the only model examined here that was developed for use in numerical weather prediction. The response to the positive SST trend forcing pattern is an overall surface warming over the world's land areas with substantial regional variations that are in part reproduced in runs forced with a globally uniform SST trend forcing. The precipitation response to the trend forcing is weak in all the models

Prospective Latin American cohort evaluating outcomes of patients with COVID-19 and abnormal liver tests on admission

Introduction & objectives: The independent effect of liver biochemistries as a prognostic factor in patients with COVID-19 has not been completely addressed. We aimed to evaluate the prognostic value of abnormal liver tests on admission of hospitalized patients with COVID-19. Materials & methods: We performed a prospective cohort study including 1611 hospitalized patients with confirmed SARS-CoV-2 infection from April 15, 2020 through July 31, 2020 in 38 different Hospitals from 11 Latin American countries. We registered clinical and laboratory parameters, including liver function tests, on admission and during hospitalization. All patients were followed until discharge or death. We fit multivariable logistic regression models, further post-estimation effect through margins and inverse probability weighting. Results: Overall, 57.8% of the patients were male with a mean age of 52.3 years, 8.5% had chronic liver disease and 3.4% had cirrhosis. Abnormal liver tests on admission were present on 45.2% (CI 42.7–47.7) of the cohort (n = 726). Overall, 15.1% (CI 13.4–16.9) of patients died (n = 244). Patients with abnormal liver tests on admission presented higher mortality 18.7% (CI 15.9–21.7), compared to those with normal liver biochemistries 12.2% (CI 10.1–14.6); P 30. Conclusions: The presence of abnormal liver tests on admission is independently associated with mortality and severe COVID-19 in hospitalized patients with COVID-19 infection and may be used as surrogate marker of inflammation.Fil: Mendizabal, Manuel. Universidad Austral. Hospital Universitario Austral; ArgentinaFil: Piñero, Federico. Universidad Austral. Hospital Universitario Austral; ArgentinaFil: Ridruejo, Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Anders, Margarita. Hospital Aleman; ArgentinaFil: Silveyra, María Dolores. Sanatorio Anchorena; ArgentinaFil: Torre, Aldo. Centro Médico ABC; MéxicoFil: Montes, Pedro. Hospital Nacional Daniel A. Carrión; PerúFil: Urzúa, Alvaro. Hospital Clínico de la Universidad de Chile; ChileFil: Pages, Josefina. Universidad Austral. Hospital Universitario Austral; ArgentinaFil: Toro, Luis G.. Hospitales de San Vicente Fundación de Medellín y Rionegro; ColombiaFil: Díaz, Javier. Hospital Nacional Edgardo Rebagliati Martins; PerúFil: Gonzalez Ballerga, Esteban. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Miranda Zazueta, Godolfino. Instituto Nacional de Ciencias Médicas y Nutrición; MéxicoFil: Peralta, Mirta. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas "Dr. Francisco Javier Muñiz"; ArgentinaFil: Gutiérrez, Isabel. Centro Médico ABC; MéxicoFil: Michelato, Douglas. Hospital Especializado en Enfermedades Infecciosas Instituto Couto Maia; BrasilFil: Venturelli, Maria Grazia. Hospital Nacional Guillermo Almenara Irigoyen; PerúFil: Varón, Adriana. Fundación Cardio-Infantil; ColombiaFil: Vera Pozo, Emilia. Hospital Regional Dr. Teodoro Maldonado Carbo; EcuadorFil: Tagle, Martín. Clínica Anglo-Americana; PerúFil: García, Matías. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Tassara, Alfredo. Hospital Aleman; ArgentinaFil: Brutti, Julia. Sanatorio Anchorena; ArgentinaFil: Ruiz García, Sandro. Hospital de Víctor Lazarte Echegaray; PerúFil: Bustios, Carla. Clínica Delgado; PerúFil: Escajadillo, Nataly. Hospital Nacional Almanzor Aguinaga Asenjo; PerúFil: Macias, Yuridia. No especifíca;Fil: Higuera de la Tijera, Fátima. Hospital General de México “Dr. Eduardo Liceaga"; MéxicoFil: Gómez, Andrés J.. Hospital Universitario Fundación Santa Fé de Bogotá; ColombiaFil: Dominguez, Alejandra. Hospital Padre Hurtado; ChileFil: Castillo Barradas, Mauricio. Hospital de Especialidades del Centro Médico Nacional La Raza; MéxicoFil: Contreras, Fernando. No especifíca;Fil: Scarpin, Aldana. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Schinoni, Maria Isabel. Hospital Alianza; BrasilFil: Toledo, Claudio. Universidad Austral de Chile; ChileFil: Girala, Marcos. Universidad Nacional de Asunción; ParaguayFil: Mainardi, Victoria. Hospital Central De las Fuerzas Armadas; UruguayFil: Sanchez, Abel. Hospital Roosevelt; GuatemalaFil: Bessone, Fernando. Provincia de Santa Fe. Ministerio de Salud y Medio Ambiente - Rosario. Hospital Provincial del Centenario; ArgentinaFil: Rubinstein, Fernando Adrian. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Silva, Marcelo Oscar. Universidad Austral. Hospital Universitario Austral; Argentin

Recent subsurface North Atlantic cooling trend in context of Atlantic decadal-to-multidecadal variability

The spatiotemporal structure of the recent decadal subsurface cooling trend in the North Atlantic Ocean is analyzed in the context of the phase reversal of Atlantic multidecadal variability. A vertically integrated ocean heat content (HC) Atlantic Multidecadal Oscillation index (AMO-HC) definition is proposed in order to capture the thermal state of the ocean and not just that of the surface as in the canonical AMO SST-based indices. The AMO-HC (5–657 m) index (defined over the area, 0°N–60°N, 5°W–75°W) indicates that: (1) The traditional surface AMO index lags the heat content (and subsurface temperatures) with the leading time being latitude-dependent. (2) The North Atlantic subsurface was in a warming trend since the mid-1980s to the mid-2000s, a feature that was also present at the surface with a lag of 3 years. (3) The North Atlantic subsurface is in a cooling trend since the mid-2000s with significant implications for predicting future North Atlantic climate. The spatial structure of decadal trends in upper-ocean heat content (5–657 m) in the North Atlantic prior to and after 2006 suggests a link with variability of the Gulf Stream–Subpolar Gyre system. The Gulf Stream leads variability in upper-ocean heat content over the Subpolar region by ∼13 years, and the lead increases from east to west from the Iceland Basin to the Irminger Sea to the Labrador Sea. The similarity between the structure of decadal mean anomalies, their change and trends in upper-ocean heat content and salinity in the North Atlantic and anomalies associated with a Gulf Stream index is striking. In this scheme, the displacements of the Gulf Stream–North Atlantic Current systems and their interactions with the Subpolar Gyre, as part of the meridional overturning circulation, have a decisive role for imposing decadal variability in both the Ocean and hydroclimate over the neighbouring continents

Climatología

En: Atlas del patrimonio natural, histórico y cultural de Veracruz ; Enrique Florescano, Juan Ortíz Escamilla, coordinadores. México : Gobierno del Estado de Veracruz : Comisión del Estado de Veracruz para la Conmemoración de la Independencia Nacional y la Revolución Mexicana : Universidad Veracruzana, 2010. v. 1, p. 65-84. ISBN 978607951316

Índices de cambio climático y análisis de variabilidad en el estado de Veracruz, México

Ponencia presentada en: VII Congreso de la Asociación Española de Climatología: clima, ciudad y ecosistemas, celebrado en Madrid entre el 24 y 26 de noviembre de 2010.[ES]Se presenta un análisis de la señal del cambio climático y la variabilidad climática en el estado de Veracruz, México. El estudio de variabilidad natural se centra en detectar las variaciones de la precipitación debidas a teleconexiones con oscilaciones atmosféricas, como El Niño-Oscilación del Sur, (ENSO) Oscilación Decadal del Pacífico (PDO), Oscilación del Ártico (AO) y la Oscilación del Atlántico Norte (NAO). Para detectar la señal del cambio climático se utilizaron los índices del Grupo de Expertos en Detección e Índices de Cambio Climático (ETCCDI). Los resultados muestran evidencia de condiciones más cálidas en años recientes, aumento en la frecuencia de días calurosos y disminución de los días frescos. En la precipitación no se perciben cambios significativos en los registros anuales o en la ocurrencia de episodios extremos, sin embargo, en la mayor parte del estado la lluvia tiende a concentrarse en un menor período.[EN]An analysis on climate variability and change over the state of Veracruz, Mexico is presented. The study of natural variability is focused on detecting relationship with atmospheric oscillations. Thus, for this purpose, we analyze El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Arctic Oscillation (AO) and North Atlantic Oscillation (NAO), finding almost no significant relationship. Regional climate change signals were evaluated using the methodology proposed by the Expert Team on Climate Change Detection and Indices (ETCCDI). The results show evidence pointing to warmer conditions in recent years, with an increased frequency of hot days and a decrease on cool days. For precipitation extreme indices no significant changes where estimated on annual basis, although a tendency to temporal concentration of rainfall was found.El financiamiento fue otorgado por el Programa Universitario de Cambio Climático de la Universidad Veracruzana y con becas del Consejo Nacional de Ciencia y Tecnología y la Secretaría de Educación Pública (México)