Estimating the Spatial Distribution of Precipitation in Iceland Using a Linear Model of Orographic Precipitation

Abstract A linear model of orographic precipitation that includes airflow dynamics, condensed water advection, and downslope evaporation is adapted for Iceland. The model is driven using coarse-resolution 40-yr reanalysis data from the European Centre for Medium-Range Weather Forecasts (ERA-40) over the period 1958–2002. The simulated precipitation is in good agreement with precipitation observations accumulated over various time scales, both in terms of magnitude and distribution. The results suggest that the model captures the main physical processes governing orographic generation of precipitation in the mountains of Iceland. The approach presented in this paper offers a credible method to obtain a detailed estimate of the distribution of precipitation in mountainous terrain for various conditions involving orographic generation of precipitation. It appears to be of great practical value to the hydrologists, glaciologists, meteorologists, and climatologists.

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A Diagnostic Study of Waves on the Tropopause

Journal of the Atmospheric Sciences ◽

10.1175/jas3800.1 ◽

2006 ◽

Vol 63 (12) ◽

pp. 3315-3332 ◽

Cited By ~ 8

Author(s):

Yoshihiro Tomikawa ◽

Kaoru Sato ◽

Theodore G. Shepherd

Keyword(s):

Phase Velocity ◽

Wave Theory ◽

Finite Depth ◽

Reanalysis Data ◽

Edge Wave ◽

Diagnostic Study ◽

Weather Forecasts ◽

Medium Range ◽

The Vertical Distribution ◽

Good Agreement

The spatial structure and phase velocity of tropopause disturbances localized around the subpolar jet in the Southern Hemisphere are investigated using 6-hourly European Centre for Medium-Range Weather Forecasts reanalysis data covering 15 yr (1979–93). The phase velocity and phase structure of the tropopause disturbances are in good agreement with those of an edge wave vertically trapped at the tropopause. However, the vertical distribution of the ratio of potential to kinetic energy exhibits maxima above and below the tropopause and a minimum around the tropopause, in contradiction to edge wave theory for which the ratio is unity throughout the troposphere and stratosphere. This difference in vertical structure between the observed tropopause disturbances and edge wave theory is attributed to the effects of a finite-depth tropopause together with the next-order corrections in Rossby number to quasigeostrophic dynamics.

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Spatial-Temporal Pattern Changes of UTCI in the China-Pakistan Economic Corridor in Recent 40 Years

Atmosphere ◽

10.3390/atmos11080858 ◽

2020 ◽

Vol 11 (8) ◽

pp. 858

Author(s):

Di Zeng ◽

Jinkui Wu ◽

Yaqiong Mu ◽

Mingshan Deng ◽

Yanqiang Wei ◽

...

Keyword(s):

Thermal Environment ◽

Linear Trend ◽

Temporal Variations ◽

Reanalysis Data ◽

Climate Index ◽

Positive Trend ◽

Growth Trend ◽

Weather Forecasts ◽

European Centre ◽

Medium Range

This paper investigated the spatial and temporal variations of the Universal Thermal Climate Index (UTCI) of the China-Pakistan Economic Corridor (CPEC) from 1979 to 2018. The European Centre for Medium-Range Weather Forecasts Re-Analysis-Interim (ERA-Interim) reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF) is selected for UTCI calculation in the region and analyzed by a linear trend and correlation analysis. The results showed that (1) the UTCI of CPEC is decreased with the increase of latitude and altitude. There is obvious spatial heterogeneity in the seasonal scale and the spatial distribution of different thermal stress categories. (2) UTCI generally exhibited a positive trend of 0.33 °C/10a over the past 40 years, and the seasonal variation characteristics of UTCI show an upward trend in all four seasons, of which spring is the fastest. On the space scale, the growth trend has significant spatial variations. (3) Temperature has a positive correlation with UTCI. The influence of temperature on UTCI is greater than that of wind speed. The results of this study will be helpful for regional planning and also contribute to comprehending the characteristics of the thermal environment in CPEC.

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Evento de Precipitação Intensa Associado às Perturbações Ondulatórias dos Alísios Sobre o Estado de Alagoas.

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v13.07.p3195-3205 ◽

2020 ◽

Vol 13 (07) ◽

pp. 3195

Author(s):

Matheus José Arruda Lyra ◽

Ismael Guidson Farias Freitas ◽

Dimas De Barros Santiago

Keyword(s):

Reanalysis Data ◽

Wave Disturbance ◽

Precipitation Event ◽

Trade Winds ◽

Climatological Data ◽

Weather Forecasts ◽

Global Era ◽

Medium Range ◽

Strong Convection ◽

High Level

O estudo teve como objetivo analisar a forte convecção provocada por uma Perturbação Ondulatória dos Alísios (POA) sobre o estado de Alagoas no dia 27 de maio de 2017. A análise e previsão de sistemas dessa magnitude desperta interesse devido os fenômenos adversos provocados e consequências à população. Foram utilizados dados de reanálise global ERA Interim fornecidos pelo European Centre for Medium-Range Weather Forecasts (ECMWF) com resolução espacial de 0,75º de latitude x 0,75º de longitude. Estes dados foram utilizados no software OpenGrADS para plotagem dos campos meteorológicos para a análise sinótica. Os dados referentes à precipitação acumulada foram fornecidos pela Secretaria de Estado do Meio Ambiente e dos Recursos Hídricos (SEMARH) a partir de 25 estações meteorológicas espalhadas por Alagoas. A perturbação se desenvolveu após a passagem de um sistema frontal que atingiu o Nordeste do Brasil alguns dias antes. O sistema sinótico pôde ser observado no campo de pressão à nível do mar e através das linhas de correntes em baixos níveis (925 e 850hPa) entre os dias 26 e 27, onde o eixo do cavado se concentrou sobre o estado de Alagoas. Os campos do fluxo de umidade integrado na vertical indicaram valores bastante elevados provenientes do Atlântico, adentrando Alagoas entre os dias 25 e 27. Através da análise da série de dados climatológica, maio de 2017 registrou o terceiro maior pico de pluviometria (692mm/24h), onde somente no dia 27 foram registrados 173mm/24h, o que correspondeu à cerca de 25% da média histórica. Intense Precipitation Event Provoked by the Wave Disturbance of Trade Winds Over the Alagoas State A B S T R A C TThe main objective of this study was to analyze the Wave Disturbance of Trade Winds (WDTW) dynamics that provoked strong rainfall over the Alagoas state on May 27 of 2017. The analysis and systems forecasting of this magnitude arouses interest due to the adverse phenomena caused and consequences to the population. Global ERA Interim reanalysis data was provided by the European Center for Medium-Range Weather Forecasts (ECMWF) with spatial resolution of 0.75º latitude x 0.75º longitude. This dataset was used in conjunction with OpenGrADS software to the meteorological fields plot for synoptic analysis. Precipitation dataset were collected from 25 meteorological stations spread across the Alagoas state provided by the State Secretary for the Environment and Water Resources (SEMARH). The disturbance developed after a frontal system passage that reached BNE a few days earlier. The synoptic system could be observed in the pressure at sea level field and through the streamlines at low levels (925 and 850hPa) between 26 and 27 of May, where the Trough axis was concentrated over Alagoas. The strong convection was also driven by a high-level Trough, lasted from 30ºS. The vertical integrated moisture flow fields indicated very high values from the Atlantic Ocean, reaching Alagoas between 25th and 27 of May. Through the analysis of climatological data, in May 2017 was registered the third highest peak of rainfall (692 mm/24h), where only on the 27th 173 mm/24h was recorded, which corresponded to the fence 25% of the historical average.Keywords: WDTW; Adverse Phenomena, Alagoas.

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An Intercomparison between ERA-Interim Reanalysis and Observed Precipitation in Northeast China

Discrete Dynamics in Nature and Society ◽

10.1155/2015/693923 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Jie Zhou ◽

Junhu Zhao

Keyword(s):

Northeast China ◽

Reanalysis Data ◽

Observation Data ◽

Precipitation Data ◽

Temporal Characteristics ◽

Weather Forecasts ◽

Medium Range ◽

Different Seasons ◽

Autumn And Winter ◽

Spatial And Temporal Characteristics

Recently, the European Center for Medium-Range Weather Forecasts (ECMWF) released a new set of reanalysis data—ERA-Interim. We make an intercomparison between ERA-Interim precipitation and observed precipitation in Northeast China. The results show that, in general, the ERA-Interim reanalysis precipitation data can describe the spatial and temporal characteristics of seasonal precipitation in Northeast China well. In terms of spatial distribution, ERA-Interim precipitation is generally consistent with the observation data in different seasons in Northeast China. There is a larger difference in the center of Northeast China than in other areas between the two kinds of data. The ERA-Interim precipitation is larger than observed precipitation in most of Northeast China. In spring, autumn, and winter, the ERA-Interim precipitation value is close to the observation one, while in summer there is a large difference in Liaoning Peninsula and Changbai Mountain between the two kinds of precipitation data. In terms of temporal characteristics, the time series of the ERA-Interim precipitation matches well with the observed precipitation in whole. In different seasons, the annual variation of the ERA-Interim precipitation is well correlated with that of the observed precipitation.

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Polar Stratospheric Clouds Detection at Belgrano II Antarctic Station with Visible Ground-Based Spectroscopic Measurements

Remote Sensing ◽

10.3390/rs13081412 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1412

Author(s):

Laura Gomez-Martin ◽

Daniel Toledo ◽

Cristina Prados-Roman ◽

Jose Antonio Adame ◽

Hector Ochoa ◽

...

Keyword(s):

Trace Gas ◽

Optical Absorption Spectroscopy ◽

Polar Stratospheric Clouds ◽

Meteorological Model ◽

Weather Forecasts ◽

Stratospheric Temperature ◽

Medium Range ◽

Stratospheric Clouds ◽

Good Agreement

By studying the evolution of the color index (CI) during twilight at high latitudes, polar stratospheric clouds (PSCs) can be detected and characterized. In this work, this method has been applied to the measurements obtained by a visible ground-based spectrometer and PSCs have been studied over the Belgrano II Antarctic station for years 2018 and 2019. The methodology applied has been validated by full spherical radiative transfer simulations, which confirm that PSCs can be detected and their altitude estimated with this instrumentation. Moreover, our investigation shows that this method is useful even in presence of optically thin tropospheric clouds or aerosols. PSCs observed in this work have been classified by altitude. Our results are in good agreement with the stratospheric temperature evolution obtained by the global meteorological model ECMWF (European Centre for Medium Range Weather Forecasts) and with satellite PSCs observations from CALIPSO (Cloud-Aerosol-Lidar and Infrared Pathfinder Satellite Observations). To investigate the presence and long-term evolution of PSCs, the methodology used in this work could also be applied to foreseen and/or historical observations obtained with ground-based spectrometers such e. g. those dedicated to Differential Optical Absorption Spectroscopy (DOAS) for trace gas observation in Arctic and Antarctic sites.

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HOAPS and ERA-Interim precipitation over sea: Validation against shipboard in-situ measurements

10.5194/amt-2016-22 ◽

2016 ◽

Author(s):

Karl Bumke ◽

Gert König-Langlo ◽

Julian Kinzel ◽

Marc Schröder

Keyword(s):

Reanalysis Data ◽

Data Sets ◽

Weather Forecasts ◽

Rain Gauges ◽

Medium Range ◽

Temporal And Spatial ◽

The Tropics ◽

Along Track ◽

Spatial Threshold

Abstract. The satellite derived HOAPS (Hamburg Ocean Atmosphere Parameters and Fluxes from Satellite data) and ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-Interim reanalysis data sets have been validated against in-situ precipitation measurements from ship rain gauges and optical disdrometers over the open-ocean by applying a statistical analysis for binary forecasts. For this purpose collocated pairs of data were merged within a certain temporal and spatial threshold into single events, according to the satellites' overpass, the observation and the forecast times. HOAPS detects the frequency of precipitation well, while ERA-Interim strongly overestimates it, especially in the tropics and subtropics. Although precipitation rates are difficult to compare because along-track point measurements are collocated with areal estimates and the numbers of available data are limited, we find that HOAPS underestimates precipitation rates, while ERA-Interim's Atlantic-wide average precipitation rate is close to measurements. However, regionally averaged over latitudinal belts, there are deviations between the observed mean precipitation rates and ERA-Interim. The most obvious ERA-Interim feature is an overestimation of precipitation in the area of the intertropical convergence zone and the southern sub-tropics over the Atlantic Ocean. For a limited number of snow measurements by optical disdrometers it can be concluded that both HOAPS and ERA-Interim are suitable to detect the occurrence of solid precipitation.

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Estimation of multipath propagation and fade margin over Coastal area

APTIKOM Journal on Computer Science and Information Technologies ◽

10.11591/aptikom.j.csit.124 ◽

2018 ◽

Vol 3 (3) ◽

pp. 77-83

Author(s):

Falodun Falodun ◽

Omotoso Omotoso ◽

Ashidi Ashidi

Keyword(s):

Multipath Propagation ◽

Coastal Region ◽

Multipath Fading ◽

Reanalysis Data ◽

Weather Forecasts ◽

Signal Degradation ◽

Port Harcourt ◽

Medium Range ◽

Weather Parameters ◽

Anomalous Propagation

Atmospheric weather parameter is dynamic in nature, hence the need for continuous investigation of the anomalous propagation phenomenon. The coastal region is more unique in its characteristics due to the rapid and continuous variation in the weather parameters. This paper presents the results from 10 years (2006 – 2015) of reanalysis data of meteorological parameters (temperature, relative humidity and atmospheric pressure) obtained from European Center for Medium-Range Weather Forecasts (ECMWF). The data covers some selected stations in the coastal region of Nigeria namely: Port-Harcourt, Warri, Calabar, Arogbo, Oron, Yenagoa and Lagos Island at four synopsies hours of the day (6 hrs, 12 hrs, 18 hrs and 24 hrs). The resolution of the ECMWF data is 0.25 by 0.25. Radio refractivity, refractivity gradient, point refractivity and geoclimatic factor are estimated from the data. Subsequently, the results were used to deduce percentage of fade depth exceedance. The overall resultsa will assist to ascertain the level of signal degradation due to multipath fading and fade depth over the coastal regions of Nigeria

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HOAPS and ERA-Interim precipitation over the sea: validation against shipboard in situ measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-9-2409-2016 ◽

2016 ◽

Vol 9 (5) ◽

pp. 2409-2423 ◽

Cited By ~ 7

Author(s):

Karl Bumke ◽

Gert König-Langlo ◽

Julian Kinzel ◽

Marc Schröder

Keyword(s):

Reanalysis Data ◽

Data Sets ◽

Weather Forecasts ◽

Rain Gauges ◽

Medium Range ◽

Temporal And Spatial ◽

The Tropics ◽

Along Track ◽

Spatial Threshold

Abstract. The satellite-derived HOAPS (Hamburg Ocean Atmosphere Parameters and Fluxes from Satellite Data) and ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-Interim reanalysis data sets have been validated against in situ precipitation measurements from ship rain gauges and optical disdrometers over the open ocean by applying a statistical analysis for binary estimates. For this purpose collocated pairs of data were merged within a certain temporal and spatial threshold into single events, according to the satellites' overpass, the observation and the ERA-Interim times. HOAPS detects the frequency of precipitation well, while ERA-Interim strongly overestimates it, especially in the tropics and subtropics. Although precipitation rates are difficult to compare because along-track point measurements are collocated with areal estimates and the number of available data are limited, we find that HOAPS underestimates precipitation rates, while ERA-Interim's Atlantic-wide average precipitation rate is close to measurements. However, when regionally averaged over latitudinal belts, deviations between the observed mean precipitation rates and ERA-Interim exist. The most obvious ERA-Interim feature is an overestimation of precipitation in the area of the intertropical convergence zone and the southern subtropics over the Atlantic Ocean. For a limited number of snow measurements by optical disdrometers, it can be concluded that both HOAPS and ERA-Interim are suitable for detecting the occurrence of solid precipitation.

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Dynamical downscaling of precipitation in Iceland 1961–2006

Hydrology Research ◽

10.2166/nh.2010.132 ◽

2010 ◽

Vol 41 (3-4) ◽

pp. 153-163 ◽

Cited By ~ 1

Author(s):

Ólafur Rögnvaldsson ◽

Jóna Finndís Jónsdóttir ◽

Haraldur Ólafsson

Keyword(s):

Dynamical Downscaling ◽

Atmospheric Flow ◽

Weather Forecasts ◽

Model Driven ◽

Ice Caps ◽

Mm5 Model ◽

Simulated Precipitation ◽

Medium Range ◽

Liquid Precipitation ◽

Better Than

Atmospheric flow over Iceland has been simulated for the period January 1961 to July 2006, using the mesoscale MM5 model driven by initial and boundary data from the European Centre for Medium Range Weather Forecasts (ECMWF). Firstly, the simulated precipitation is compared to estimates derived from mass balance measurements on the Icelandic ice caps. It is found that the simulated precipitation compares favourably with the observed winter balance, in particular for Hofsjökull, where corrections to take liquid precipitation and/or winter ablation into account have been made, and for the outlet glaciers Dyngjujökull and Brúarjökull. Secondly, the model output is used as input to the WaSiM hydrological model to calculate and compare the runoff with observed runoff from six watersheds in Iceland. It is found that model results compare favourably with observations. Overall, the MM5 V3–7 is somewhat better than the MM5 V3–5. The V3–7 is drier than V3–5 on upstream slopes.

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Mapping Flash Floods in Iraq by Using GIS

Environmental Sciences Proceedings ◽

10.3390/ecas2021-10696 ◽

2021 ◽

Vol 8 (1) ◽

pp. 39

Author(s):

Ali Raheem Al-Nassar ◽

Hussein Kadhim

Keyword(s):

Daily Precipitation ◽

Flash Floods ◽

Reanalysis Data ◽

The Other ◽

Dynamical Analysis ◽

Total Rainfall ◽

Weather Forecasts ◽

The Third ◽

Medium Range ◽

Precipitation Records

This study aims to investigate flash floods in Iraq by plotting the cartographic maps by using synoptic and dynamical analysis of meteorological reanalysis data obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF) and statistical analysis of daily precipitation records from the Iraqi Meteorological and Seismology Organization for selected Iraqi stations (Mosul, Kirkuk, Khanaqin, Baghdad and Al-Rutba, Al-Hayy, Al-Nasiriyah, and Basra), as well as the use of geographic information system (GIS) techniques. Three models create to investigate and map flash floods in Iraq. The results of the first model (the longest period of time) shows that the station of Mosul record the longest period for a rainstorm, 9 days in 2014, while the lowest period was in Rutba, 6 days in 2012, and the other stations varied between these two stations. The results of the second model (the highest total rainfall), present that Kirkuk station recorded the highest amount of rain (117.2 mm in 2013), while Al-Rutba station, 47.2 mm in 2011, the lowest station. Finally, the results of the third model (the highest frequency of rainstorms per month) shows that the lowest frequency of rainstorms per month was in Basra, 29 rainstorms in 2009, while Mosul station has 40 rainstorms in 2007 and the other stations within these two values.

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