scholarly journals District level value-added dynamical-synoptic forecast system for rainfall

MAUSAM ◽  
2021 ◽  
Vol 57 (2) ◽  
pp. 209-220
Author(s):  
B. LAL ◽  
O. P. SINGH ◽  
ONKARI PRASAD ◽  
S. K. ROY BHOWMIK ◽  
S. R. KALSI ◽  
...  
Keyword(s):  
Weather Forecasting ◽  
Value Added ◽  
India Meteorological Department ◽  
Southwest Monsoon ◽  
District Level ◽  
New Delhi ◽  
Weather Forecasts ◽  
Synoptic Weather ◽  
Mm5 Model ◽  
Medium Range

Lkkj & bl ’kks/k&Ik= esa o"kkZ ls lacaf/kr ftyk Lrjh; ekuksa ij vk/kkfjr xfrdh; flukfIVd iwokZuqeku dh Ik)fr vkSj mlds iz;ksxkRed ifj.kkeksa dks izLrqr fd;k x;k gSA blds igys bl rduhd dk mi;ksx o"kZ 2005 dh ekulwu iwoZ dh _rq] nf{k.kh if’peh ekulwu _rq vkSj ekulwu ds Ik’pkr dh _rq ds nkSjku gqbZ ftysokj o"kkZ dk iwokZuqeku yxkus ds fy, fd;k x;k FkkA mDr 2005 ds iwokZuqeku ds fy, Vh-&80],e- ,e- 5] jk"Vªh; e/; vof/k ekSle iwokZuqeku dsUnz ¼,u- lh- ,e- vkj- MCY;w- ,Q-½ ds- bZ- Vh- ,- vkSj Hkkjr ekSle foKku foHkkx esa dk;Z’khy ,e- ,e- 5 xfrdh; fun’kksZa dk lefUor #Ik ls mi;ksx fd;k x;k FkkA iwokZuqeku esa lefUor #Ik ls ;ksxnku nsus okys lHkh fun’kksZa ds ekuksa dk vyx&vyx ewY;kadu djds muls izkIr gq, o"kkZ ds iwokZuqekuksa dk mi;ksx djds xfrdh; iwokZuqeku rS;kj fd;k x;k gSA ifjpkyu y{k.kksa] m/okZ/kj osx] mixzg ls izkIr lwpuk flukfIVd pkVksZa vkSj tyok;q foKku vkfn tSls vU; fun’kksZa dk vkdyu djds xfrdh; iwokZuqekuksa dks eku vk/kkfjr ¼osY;w ,fMM ½ flukfIVd ekSle iwokZuqekuksa esa ifjofrZr fd;k x;k gSA o"kZ 2005 esa fd, x, iwokZuqeku ds vuqHko ls ;g irk pyk gS fd lefUor #Ik ls ;ksxnku nsus okys fun’kksZa ls vyx&vyx izkIr gq, o"kkZ ds iwokZuqekuksa dh fuiq.krk dh rqyuk esa eku&vk/kkfjr ¼osY;w ,fMM ½ xfrdh; flukfIVd iz.kkyh ds 24, 48, 72 ?kaVksa ds ftyk Lrjh; o"kkZ ds iwokZuqeku dgha vf/kd fuiq.krk ls rS;kj fd, tk ldrs gSaA The paper presents the methodology and trial results of the district level value-added dynamical-synoptic forecast for rainfall. The technique was tried for forecasting districtwise rainfall during Pre-monsoon, Southwest Monsoon and Post monsoon seasons of 2005. The constituent dynamical models were T-80, MM5, ETA of the National Centre for Medium Range Weather Forecasting (NCMRWF) and the MM5 model operational at India Meteorological Department, New Delhi. The dynamical predictions were prepared using the rainfall predictions of the constituent models by assigning different weights. The dynamical predictions were converted into value-added synoptic-weather forecasts by taking into account other inputs like circulation features, vertical velocity, satellite information, synoptic charts and climatology etc. The experience during 2005 has shown that the value-added dynamical-synoptic system can produce 24, 48, 72 hours district level rainfall forecast of greater skill than the skills of the constituent models.

scholarly journals Value addition in district level dynamical forecast during monsoon depressions and storms

MAUSAM ◽  
2021 ◽  
Vol 58 (1) ◽  
pp. 1-8
Author(s):  
O. P. SINGH ◽  
B. LAL ◽  
ONKARI PRASAD
Keyword(s):  
Sea Level ◽  
Heavy Rainfall ◽  
Rainfall Amount ◽  
District Level ◽  
Value Addition ◽  
Maximum Rainfall ◽  
Mean Sea Level ◽  
Weather Forecasts ◽  
Medium Range ◽  
Monsoon Depressions

ABSTRACT. The trials of district level forecasts yielded encouraging results during 2005 monsoon. The purpose of this paper is to document the methodology followed in the value addition during the periods of monsoon depressions and storms. The focus is on the use of Mean Sea Level (MSL) positions and the 850 hPa circulation features predicted by different model centres, especially the European Centre for Medium-Range Weather Forecasts (ECMWF). The ECMWF-predicted 72 hr MSL position of the monsoon depression centre was found to be significantly correlated to the actual position of the system and the central location of the realized rainfall zone associated with the system. Even the predicted location of the system at 850 hPa by the ECMWF has been found useful in identifying the districts that received heaviest rainfall associated with the monsoon systems.MM5 and T-80 – predicted locations of the system at 850 hPa yielded lower correlations with the location of the actual rainfall zone associated with the system. As ECMWF – predicted rainfall was not available the rainfall predicted by MM5 and T-80 were used in the computations of the correlations with actual rainfall amounts associated with monsoon depressions and storms. The correlations between MM5 and T-80 – predicted average and maximum rainfall associated with systems and corresponding actual were poor. Though it is not difficult to identify the districts that are likely to be affected by the heavy rainfall associated with monsoon depressions/storms, the prediction of exact rainfall amount for each district (beyond heavy, very heavy or exceptionally heavy categories) is difficult from the model outputs which makes such forecasts a very challenging task. Therefore, the value addition using other inputs such as satellite information, synoptic charts, climatology etc. are very useful in the prediction of rainfall amounts associated with monsoon systems.

scholarly journals Technical and operational characteristics of GPS radiosounding system in the upper air network of IMD

MAUSAM ◽  
2021 ◽  
Vol 62 (3) ◽  
pp. 403-416
Author(s):  
GAJENDRA KUMAR ◽  
RANJU MADAN ◽  
K.C. SAIKRISHNAN ◽  
S.K. KUNDU ◽  
P.K. JAIN
Keyword(s):  
Global Positioning System ◽  
Weather Forecasting ◽  
Quality Change ◽  
Weather Forecasts ◽  
National Centre ◽  
Operational Characteristics ◽  
Global Positioning ◽  
Medium Range ◽  
Black List

In recent years, the upper air radiosounding system based on Global Positioning System (GPS) is used as an effective method. GPS receiving device in a Radiosonde improves observation accuracy, allowing simplification of ground equipment. To get improved quality of upper air data, ten stations have been upgraded with new upper air systems based on GPS. This paper describes the upper air radiosounding system that adopts the GPS. After the introduction of GPS Radiosonde in the network at 10 places, data quality has improved substantially at these stations, which has been validated by National Centre for Medium Range Weather Forecasting (NCMRWF) and European Centre for Medium-Range Weather Forecasts (ECMWF). In all cases the quality change has been remarkable and as a result black list tag is removed by ECMWF for the Indian GPS stations.

Knowing Their Place: The Blue Hill Observatory and the Value of Local Knowledge in an Era of Synoptic Weather Forecasting, 1884–1894

2016 ◽  
Vol 29 (3) ◽  
pp. 305-346 ◽  
Author(s):  
James Bergman
Keyword(s):  
Local Knowledge ◽  
Weather Forecasting ◽  
Scale Up ◽  
Weather Forecast ◽  
Weather Forecasts ◽  
Synoptic Weather ◽  
Observation Network ◽  
Meteorological Observatory ◽  
History Of ◽  
The U.S

ArgumentThe history of meteorology has focused a great deal on the “scaling up” of knowledge infrastructures through the development of national and global observation networks. This article argues that such efforts to scale up were paralleled by efforts to define a place for local knowledge. By examining efforts of the Blue Hill Meteorological Observatory, near Boston, Massachusetts, to issuelocalweather forecasts that competed with the centralized forecasts of the U.S. Signal Service, this article finds that Blue Hill, as a user of the Signal Service's observation network, developed a new understanding of local knowledge by combining local observations of the weather with the synoptic maps afforded by the nationwide telegraph network of the U.S. Signal Service. Blue Hill used these forecasts not only as a service, but also as evidence of the superiority of its model of local forecasting over the Signal Service's model, and in the process opened up larger questions about the value of a weather forecast and the value of different kinds of knowledge in meteorology.

scholarly journals Using a Business Process Model as a Central Organizing Construct for an Undergraduate Weather Forecasting Course

2012 ◽  
Vol 93 (5) ◽  
pp. 697-709 ◽  
Author(s):  
John M. Lanicci
Keyword(s):  
Business Process ◽  
Process Model ◽  
Weather Forecasting ◽  
Value Added ◽  
Point Of View ◽  
Business Process Model ◽  
Weather Forecasts ◽  
Case Study Analysis ◽  
Final Project ◽  
Weather Information

For the last five years, the author has employed a business process model as a central organizing construct for the senior-level Forecasting Techniques course at Embry- Riddle Aeronautical University's Daytona Beach, Florida, campus. The process model allows weather analysis and forecasting to be examined as both a scientific process and a business operation, with emphasis on employing a user-focused approach. The use of the model arose from the need for an organizing context for the students, mostly seniors applying their knowledge from previous coursework, most of whom are learning to make their first weather forecasts. The process model used in the present version of the course evolved from one originally developed by the U.S. Air Force to describe weather information's value-added contributions to daily operations. The model consists of two major interrelated components: the weather information processing cycle (WIPC) and the provider–user relationship (PUR). The WIPC describes the analysis/forecast process from the scientific point of view, whereas the PUR examines the relationship between the provider and user of meteorological information. The WIPC uses familiar concepts such as data collection, analysis, and prediction, whereas the PUR introduces the students to complex (and seldom taught) topics such as user requirements and mission analyses. The process model also provides a framework for the final project, a case-study analysis that emphasizes not only the weather associated with the event but also its resulting impact on the affected population.

How Global Warming Changes the Difficulty of Synoptic Weather Forecasting

2020 ◽  
Author(s):  
Sebastian Scher ◽  
Gabriele Messori
Keyword(s):  
Global Warming ◽  
Temperature Gradient ◽  
Prediction Model ◽  
21St Century ◽  
Weather Forecasting ◽  
Weather Prediction ◽  
Meridional Temperature Gradient ◽  
Weather Forecasts ◽  
Synoptic Weather ◽  
Business As Usual

<p>Little is known on whether and how global warming may affect the atmosphere's predictability and thus our ability to produce accurate weather forecasts. Here, we combine a climate and an ensemble weather prediction model to show that, in a business-as-usual 21st century setting, global warming could significantly change the predictability of the atmosphere, defined here via the expected error of weather predictions. Predictability of synoptic weather situations could significantly increase, especially in the Northern Hemisphere. This can be explained by a decrease in the meridional temperature gradient, which seems to control the inter-annual variability of atmospheric predictability. Contrarily, summertime predictability of weekly rainfall sums might significantly decrease in most regions.</p>

Dynamical downscaling of precipitation in Iceland 1961–2006

2010 ◽  
Vol 41 (3-4) ◽  
pp. 153-163 ◽  
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.

scholarly journals Ship-Mounted Real-Time Surface Observational System on board Indian Vessels for Validation and Refinement of Model Forcing Fields*

2013 ◽  
Vol 30 (3) ◽  
pp. 626-637 ◽  
Author(s):  
R. Harikumar ◽  
T. M. Balakrishnan Nair ◽  
G. S. Bhat ◽  
Shailesh Nayak ◽  
Venkat Shesu Reddem ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Southern Ocean ◽  
Real Time ◽  
Weather Forecasting ◽  
Ocean Model ◽  
Weather Forecasts ◽  
European Centre ◽  
National Centre ◽  
Medium Range ◽  
Weather Stations

Abstract A network of ship-mounted real-time Automatic Weather Stations integrated with Indian geosynchronous satellites [Indian National Satellites (INSATs)] 3A and 3C, named Indian National Centre for Ocean Information Services Real-Time Automatic Weather Stations (I-RAWS), is established. The purpose of I-RAWS is to measure the surface meteorological–ocean parameters and transmit the data in real time in order to validate and refine the forcing parameters (obtained from different meteorological agencies) of the Indian Ocean Forecasting System (INDOFOS). Preliminary validation and intercomparison of analyzed products obtained from the National Centre for Medium Range Weather Forecasting and the European Centre for Medium-Range Weather Forecasts using the data collected from I-RAWS were carried out. This I-RAWS was mounted on board oceanographic research vessel Sagar Nidhi during a cruise across three oceanic regimes, namely, the tropical Indian Ocean, the extratropical Indian Ocean, and the Southern Ocean. The results obtained from such a validation and intercomparison, and its implications with special reference to the usage of atmospheric model data for forcing ocean model, are discussed in detail. It is noticed that the performance of analysis products from both atmospheric models is similar and good; however, European Centre for Medium-Range Weather Forecasts air temperature over the extratropical Indian Ocean and wind speed in the Southern Ocean are marginally better.

scholarly journals Impact of AMDAR observations from Lufthansa aircraft on Global Analysis - Forecast System

MAUSAM ◽  
2021 ◽  
Vol 61 (2) ◽  
pp. 213-220
Author(s):  
SURYA K. DUTTA ◽  
MUNMUN DAS GUPTA ◽  
V. S. PRASAD
Keyword(s):  
Weather Forecasting ◽  
Positive Impact ◽  
Global Analysis ◽  
India Meteorological Department ◽  
Forecasting Model ◽  
Forecast System ◽  
National Centre ◽  
Medium Range ◽  
Special Arrangement

     AMDAR observations from Lufthansa and Lufthansa cargo aircrafts in BUFR format (with header IUADOI EGGR and IUAHOI EGRR) were made available to India Meteorological Department (IMD) and in turn to National Centre for Medium Range Weather Forecasting (NCMRWF) under special arrangement for a period of two weeks w.e.f. 14th May 2008. These data have been assimilated at NCMRWF (National Centre for Medium Range Weather Forecasting) model for the period 14th - 31st May, 2008 to assess its impact on NWP. Use of these observations gave some positive impact on NWP systems.

scholarly journals The Stratospheric Extension of the Canadian Global Deterministic Medium-Range Weather Forecasting System and Its Impact on Tropospheric Forecasts

2012 ◽  
Vol 140 (6) ◽  
pp. 1924-1944 ◽  
Author(s):  
Martin Charron ◽  
Saroja Polavarapu ◽  
Mark Buehner ◽  
P. A. Vaillancourt ◽  
Cécilien Charette ◽  
...  
Keyword(s):  
Weather Forecasting ◽  
Initial Conditions ◽  
Forecast Model ◽  
Forecast Skill ◽  
Weather Forecasts ◽  
Medium Range ◽  
Summer Hemisphere ◽  
Forecasting System ◽  
Winter Hemisphere ◽  
Radiation Scheme

Abstract A new system that resolves the stratosphere was implemented for operational medium-range weather forecasts at the Canadian Meteorological Centre. The model lid was raised from 10 to 0.1 hPa, parameterization schemes for nonorographic gravity wave tendencies and methane oxidation were introduced, and a new radiation scheme was implemented. Because of the higher lid height of 0.1 hPa, new measurements between 10 and 0.1 hPa were also added. This new high-top system resulted not only in dramatically improved forecasts of the stratosphere, but also in large improvements in medium-range tropospheric forecast skill. Pairs of assimilation experiments reveal that most of the stratospheric and tropospheric forecast improvement is obtained without the extra observations in the upper stratosphere. However, these observations further improve forecasts in the winter hemisphere but not in the summer hemisphere. Pairs of forecast experiments were run in which initial conditions were the same for each experiment but the forecast model differed. The large improvements in stratospheric forecast skill are found to be due to the higher lid height of the new model. The new radiation scheme helps to improve tropospheric forecasts. However, the degree of improvement seen in tropospheric forecast skill could not be entirely explained with these purely forecast experiments. It is hypothesized that the cycling of a better model and assimilation provide improved initial conditions, which result in improved forecasts.

scholarly journals Verification of district level weather forecast

MAUSAM ◽  
2021 ◽  
Vol 67 (4) ◽  
pp. 829-840
Author(s):  
N. CHATTOPADHYAY ◽  
K. GHOSH ◽  
K. MALATHI ◽  
S. K. ROY BHOWMIK ◽  
K. K. SINGH
Keyword(s):  
Value Added ◽  
Weather Forecast ◽  
District Level ◽  
Mild Winter ◽  
Weather Forecasts ◽  
North East ◽  
The North ◽  
Ensemble Techniques ◽  
East Region ◽  
Weather Parameters

IMD started issuing quantitative district level weather forecast upto 5 days on operational basis from 1st June, 2008. The products comprise of quantitative forecasts for seven weather parameters, viz., rainfall, maximum and minimum temperatures, wind speed and direction, relative humidity and cloudiness. The rainfall forecast is generated  based on multi model-ensemble techniques (MME). For other parameters, ECMWF forecasts (presently IMDGFS) are used. These forecast products are further value added, by the respective MCs/RMCs and forwarded to 130 Agrometeorological Field Units (AMFUs) for preparation of weather based District Agromet Advisory Service bulletin.  This Meteorological Monograph describes the performance skill of the operational district level weather forecasts over different parts of India rainfall during monsoon and temperature during winter and summer from 2012-14.  The Monograph also highlights limitations and future scope for further improvement of the MME models. The   verification results show weather forecasts are reasonably accurate and value addition has improved the accuracy of model forecast. Though the MME model could predict the weather in hill regions in the North but in other regions having some hilly areas, the same could not come true in respect of temperature.  North East region of the country shows very less accuracy due to its predominantly humid sub-tropical climate with hot, humid summers, severe monsoons and mild winter.  

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