Affiner votre recherche
Résultats 1-10 de 4,013
Temporal Analysis and Forecast of Surface Air Temperature: case study in Colombia
2022
Romero Leiton, Jhoana Patricia | Torres, Diego | Romero, Manuel
In this work, we study the short-term dynamics of the Surface Air Temperature (SAT) using data obtained from a meteorological station in Bogotá from 2009 to 2019 and using time series. The data that we used correspond to the monthly mean of the historical registers of SAT and three pollutants. A descriptive analysis of the data follows. Then, some predictions are obtained from two different approaches: (i) a univariate analysis of SAT through a SARIMA model, which shows a good fit; and (ii) a multivariate analysis of SAT and pollutants using a SVAR model. Suitable transformations were first applied on the original dataset to work with stationary time series. Subsequently, A SARIMA model and a VAR(2) with its associated SVAR model are estimated. Furthermore, we obtain one-year forecasts for the logarithm of SAT in both models. Our forecasts simulate the natural fluctuation of SAT, presenting peaks and valleys in months when SAT is high and low, respectively. The SVAR model allows us to identify certain shocks that affect the instant relationships among variables. These relations were studied by the impulse-response function and the VAR model variance decomposition. Although the statistical methods used in this study are classical, they continue being widely used in the environmental field, presenting god fits, and the results obtained in this study are consistent with environmental theories.
Afficher plus [+] Moins [-]PCBs [polychlorinated biphenyls], dioxins and furans in hooded merganser (Lophodytes cucullatus), common merganser (Mergus merganser) and mink (Mustela vison) collected along the St. Maurice River near La Tuque, Quebec.
1996
Champoux L.
The interaction of So2 and root-knot nematode on tomato.
1993
Khan M.R. | Khan M.W.
Predisposition of trees by air pollutants to low temperatures and moisture stress.
1995
Chappelka A.H. | Freer Smith P.H.
The non-specificity of PAN [peroxyacetyl nitrate] symptoms on tomato foliage.
1983
Lewis T. | Brennan E.
Atmospheric nitrogen deposition to the North Sea.
1994
Asman W.A.H. | Berkowicz R.
N-nitrosodimethylamine in drinking water - Using a rapid, solid-phase extraction method.
1995
Jenkins S.W.D. | Koester C.J. | Taguchi V.Y. | Wang D.T. | Palmentier J.F.P. | Hong K.P.
Chronic toxicity of an environmental contaminant mixture to young (or larval) striped bass.
1987
Mehrle P.M. | Cleveland L. | Buckler D.R.
Spatial variability in compartmental fate modelling -Linking fugacity models and GIS (Geographical information systems).
1996
Wania F.
Kinetic constraints on the in-situ remediation of soils contaminated with organic chemicals.
1995
Beck A.J. | Jones K.C.