Search results for "LATITUDE"
showing 10 items of 210 documents
The Extratropical Transition of Tropical Cyclones. Part II: Interaction with the Midlatitude Flow, Downstream Impacts, and Implications for Predictab…
2019
Abstract The extratropical transition (ET) of tropical cyclones often has an important impact on the nature and predictability of the midlatitude flow. This review synthesizes the current understanding of the dynamical and physical processes that govern this impact and highlights the relationship of downstream development during ET to high-impact weather, with a focus on downstream regions. It updates a previous review from 2003 and identifies new and emerging challenges and future research needs. First, the mechanisms through which the transitioning cyclone impacts the midlatitude flow in its immediate vicinity are discussed. This “direct impact” manifests in the formation of a jet streak …
Windowed Etas Models With Application To The Chilean Seismic Catalogs
2015
Abstract The seismicity in Chile is estimated using an ETAS (Epidemic Type Aftershock sequences) space–time point process through a semi-parametric technique to account for the estimation of parametric and nonparametric components simultaneously. The two components account for triggered and background seismicity respectively, and are estimated by alternating a ML estimation for the parametric part and a forward predictive likelihood technique for the nonparametric one. Given the geographic and seismological characteristics of Chile, the sensitivity of the technique with respect to different geographical areas is examined in overlapping successive windows with varying latitude. A different b…
Pour une véritable théorie de la latitude managériale et du gouvernement des entreprises.
1996
Le problème du contrôle des dirigeants et la notion de gouvernement des entreprises font l'objet depuis longtemps de travaux, souvent liés à des théories de l'organisation parmi les plus connues (théorie des coûts de transaction, théorie de l'agence…). Mais il semble que ces analyses, notamment parce qu'elles sont trop centrées sur les relations avec les actionnaires et négligent l'examen de la « latitude managériale », ne puissent qu'incomplètement rendre compte du statut et du comportement effectif des dirigeants. L'auteur propose ici de suivre diverses pistes pour dépasser cette situation en enrichissant les approches réductrices aujourd'hui dominantes.
Soil fungal community composition does not alter along a latitudinal gradient through the maritime and sub-Antarctic
2012
We investigated the relationships between fungal community composition, latitude and a range of physicochemical parameters in 58 soils sampled from a 2370 km latitudinal gradient between South Georgia (54 S, 38 W) in the sub-Antarctic and Mars Oasis (72 S, 68 W) on Alexander Island in the southern maritime Antarctic. Our study, which is based on approximately ten times the number of samples used in previous similar studies, indicates that latitude and its associated environmental parameters are not related to fungal community composition. Significant changes in the composition of soil fungal communities were observed in relation to gradients of the ratio of total organic carbon to nitrogen,…
Development of a general model to estimate the instantaneous, daily, and daytime net radiation with satellite data on clear-sky days
2015
Net radiation is a key variable in computing evapotranspiration and is a driving force in many other physical and biological processes. Remote sensing techniques provide an unparalleled spatial and temporal coverage of land-surface attributes, and thus several studies have attempted to estimate net radiation by combining remote sensing observations with surface and atmospheric data. However, remote sensing provides instantaneous data, when many applications and models need information at other temporal scales. In this work, a new general methodology is proposed to estimate daily and daytime net radiation and to retrieve the diurnal cycle of net radiation. Four images were acquired on differ…
A very simple model for computing global solar radiation
1990
Abstract In this paper a very simple model for predicting the daily global solar radiation at any Italian location using as input of a few extensively measured meterological parameters is proposed. In fact the daily radiation G (MJ m−2) is here correlated only with the sunshine duration s (h) and the noon altitude of the sun on the 15th of the month h n (degrees) by the following equation: G= Ks 0.5 (sin h n ) 1.15 where only one value of the factor K is used. The validity of this formula is verified fixing K = 7.8 and using the data from 34 Italian stations displaced at various latitudes, altitudes or geographical situations (inland or coastal site). The test results show that the deviatio…
Some aspects of the seasonal variation of carbon dioxide and ozone
1968
An attempt is made to estimate the seasonal source function, Q , of CO 2 on the basis of data for the biosphere, provided by Lieth, and for other sources. The variation of soil respiration appears to be the most uncertain factor. The resulting CO 2 variations in the atmosphere are calculated for horizontal exchange coefficients, K , which vary with latitude. Comparison with observations given by Bolin & Keeling shows that the results are not very sensitive with respect to the assumed variations of Q and of K with latitude. Previous results on the 0 3 budget are used to calculate seasonal variations of tropospheric 0 3 for stratospheric injection rates, and K values which vary with latitude.…
Climate indices for the Baltic states from principal component analysis
2017
Abstract. We used principal component analysis (PCA) to derive climate indices that describe the main spatial features of the climate in the Baltic states (Estonia, Latvia, and Lithuania). Monthly mean temperature and total precipitation values derived from the ensemble of bias-corrected regional climate models (RCMs) were used. Principal components were derived for the years 1961–1990. The first three components describe 92 % of the variance in the initial data and were chosen as climate indices in further analysis. Spatial patterns of these indices and their correlation with the initial variables were analyzed, and it was detected (based on correlation coefficient between principal compon…
100-millisecond Resolution for Accurate Overirradiance Measurements
2013
Cloud enhancement of sunlight results in peak irradiance well exceeding extraterrestrial levels, even at high latitudes. Values above 1.8 kW/m2 are possible in the equatorial regions. Recently, we detected bursts over 1.5 kW/m2 in Northern Europe at latitude close to 60°N. Overirradiance events (intensities much higher than 1 sun) can last tens of minutes, as well as less than 1 s. They may have caused series arcing in photovoltaic modules, leading to fires and loss of property. The accurate measurement of short bursts requires sensors with response times on the order of milliseconds. The long response times of thermopile pyranometers smooth out important details of very short-lived peaks a…
Observation of Terrestrial Gamma-Ray Flashes at Mid Latitude
2021
We present a sample of Terrestrial Gamma-ray Flashes (TGFs) observed at mid latitudes by the Atmosphere Space Interaction Monitor (ASIM). The events were detected between June 2018 and August 2020 in the latitude bands between 35° and 51° in both hemispheres, which we hereafter refer to as “mid latitudes.” The sample includes the first observations above urn:x-wiley:2169897X:media:jgrd57293:jgrd57293-math-0001 and consists of 14 events clustered in four geographical regions: north-west Atlantic and eastern USA; Mediterranean Sea; the ocean around South Africa; and north-eastern China and Siberia. We examine the characteristics of each event, both standalone and in the context of the global …