Met Data via the Internet Tim Thornton. November 2007 Smartcom Software Ltd Why use the Internet?...

Met Data via the Met Data via the InternetInternet

Tim ThorntonTim Thornton

November 2007 Smartcom Software Ltd

Why use the Internet?Why use the Internet?

There is plenty of weather data available through the There is plenty of weather data available through the official marine channels: VHF, Navtex, Shipping official marine channels: VHF, Navtex, Shipping Forecast, Weatherfax, so why use the internet?Forecast, Weatherfax, so why use the internet?




Convenience – no need to wait for the next broadcastConvenience – no need to wait for the next broadcast




Convenience – no need to wait for the next broadcastConvenience – no need to wait for the next broadcast Content – much better on the internet in terms of Content – much better on the internet in terms of

area, parameters, detail etcarea, parameters, detail etc




Convenience – no need to wait for the next broadcastConvenience – no need to wait for the next broadcast Content – much better on the internet in terms of Content – much better on the internet in terms of

area, parameters, detail etcarea, parameters, detail etc Comprehension – presentation is often easier to Comprehension – presentation is often easier to

understandunderstand


How to ConnectHow to Connect

A number of different ways to connect to A number of different ways to connect to the internet:the internet:




Broadband at homeBroadband at home Wi-Fi in the marinaWi-Fi in the marina




Broadband at homeBroadband at home Wi-Fi in the marinaWi-Fi in the marina Mobile phone in coastal watersMobile phone in coastal waters Satellite phone e.g. Iridium or Fleet Satellite phone e.g. Iridium or Fleet

offshoreoffshore


Mobile CoverageMobile CoverageVodafone Coverage- Need a good antenna to get this range- Note lower range of 3G services

Worldwide Coverage (All Networks)On all 4 GSM frequencies


FacilitiesFacilitiesServiceService VoiceVoice FaxFax TextText DataData GMDSSGMDSS CoverCover

WiFiWiFi Via VoIPVia VoIP Via netVia net NoNo 2,000,0002,000,000 NoNo MarinaMarina

GSMGSM YesYes YesYes YesYes 96009600 NoNo 10-15 miles10-15 miles

GPRSGPRS Via GSMVia GSM Via GSMVia GSM Via GSMVia GSM ~ 30,000~ 30,000 NoNo 10-15 miles10-15 miles

3G3G YesYes YesYes YesYes > 380,000> 380,000 NoNo 10-15 miles10-15 miles

IridiumIridium YesYes NoNo YesYes 24002400 NoNo GlobalGlobal

ThurayaThuraya YesYes NoNo NoNo 96009600 NoNo Med, Middle EastMed, Middle East

GlobalStGlobalStarar YesYes NoNo NoNo 96009600 NoNo OffshoreOffshore

INMARSINMARSAT CAT C NoNo Text onlyText only YesYes 6060 YesYes GlobalGlobal

INMARSINMARSAT Mini-AT Mini-MM

YesYes YesYes NoNo 24002400 NoNo OffshoreOffshore

INMARSINMARSAT Fleet AT Fleet 3333

YesYes YesYes NoNo56,000 56,000 packet, 9,600 packet, 9,600 dial-updial-up

NoNo OffshoreOffshore


Costs (UK£ inc. VAT)Costs (UK£ inc. VAT)ServiceService PurchasePurchase Monthly subMonthly sub Voice /minVoice /min Data per MegabyteData per Megabyte

WiFiWiFi < £100< £100 LowLow FreeFree FreeFree

GSMGSM £200 - £500£200 - £500 00 £0.15 - £1.10£0.15 - £1.10 £2.13 - £8.10£2.13 - £8.10

GPRSGPRS 00 00 N/AN/A £0.30 - £8.50£0.30 - £8.50

IridiumIridium £1800-£2500£1800-£2500 £0 - £25£0 - £25 £0.50-£1.75£0.50-£1.75 £56.80 - £99.50£56.80 - £99.50

ThurayaThuraya £1400£1400 £25.00£25.00 £0.50 - £1.30£0.50 - £1.30 £7.10 - £18.50£7.10 - £18.50

GlobalStarGlobalStar £800 - £1600£800 - £1600 £16.60£16.60 £0.60 - £2.50£0.60 - £2.50 £8.50 - £30.00£8.50 - £30.00

INMARSAT CINMARSAT C £1750 - £2700£1750 - £2700 00 N/AN/A £5783£5783

Mini-MMini-M £4250£4250 00 £1.60 - £2.80£1.60 - £2.80 £91 - £160£91 - £160

INMARSAT Fleet 55INMARSAT Fleet 55 £16000£16000 00 £ 1.50 - £2.30£ 1.50 - £2.30 £10.50 - £14.00 for ISDN, £20 - £26 £10.50 - £14.00 for ISDN, £20 - £26 for packetfor packet

INMARSAT Fleet 33INMARSAT Fleet 33 TBATBA 00 £ 1.50 - £2.30£ 1.50 - £2.30 £10.50 - £14.00 for ISDN, £20 - £26 £10.50 - £14.00 for ISDN, £20 - £26 for packetfor packet


How to Get DataHow to Get Data

A choice of two different ways to access the A choice of two different ways to access the data:data:

Web browsing on a PC or mobile phoneWeb browsing on a PC or mobile phone Easy to useEasy to use Masses of dataMasses of data Slow to downloadSlow to download Data not saved for offline accessData not saved for offline access


How to Get DataHow to Get Data

A choice of two different ways to access the A choice of two different ways to access the data:data:

Download data to software on your PCDownload data to software on your PC Needs special softwareNeeds special software Data more limitedData more limited Faster, cheaper download (especially if direct to Faster, cheaper download (especially if direct to

server)server) Data available offlineData available offline GRIB files often availableGRIB files often available


Sources of Internet DataSources of Internet Data

Current weather reports e.g. weather Current weather reports e.g. weather stations, weather camsstations, weather cams

Remote sensingRemote sensing Forecast mapsForecast maps Weather Portals – One stop shopsWeather Portals – One stop shops Forecast data e.g. GRIBForecast data e.g. GRIB Weather routingWeather routing Commercial services Commercial services


Weather ReportsWeather Reports

Useful for:Useful for: Seeing the current conditions before you Seeing the current conditions before you

get down to the boatget down to the boat Seeing any local effects, e.g. sea Seeing any local effects, e.g. sea

breezes, too small or too short to be breezes, too small or too short to be forecastforecast

Comparing forecasts and actualsComparing forecasts and actuals


Weather ReportsWeather Reports

Weather station reportsWeather station reports Weather buoysWeather buoys Reporting ShipsReporting Ships Weather camsWeather cams

Check the time of the weather reports.Check the time of the weather reports.

Beware of local effects, and the location of Beware of local effects, and the location of the station relative to youthe station relative to you


Met OfficeMet Office

Official Weather Stations


Weather UndergroundWeather Underground

Personal and Official Weather Stations


Weather UndergroundWeather Underground

Weather report – and data tabulated every 5 mins for personal, 1 or 3 hours for official stations


US NDBC – Ships, weather US NDBC – Ships, weather buoys etcbuoys etc

Search for all weather reports within a given distance and time Search for all weather reports within a given distance and time periodperiod

See all reports with latest dataSee all reports with latest dataSee the history of data at weather buoysSee the history of data at weather buoys


SmartMet Weather ReportsSmartMet Weather Reports


Remote SensingRemote SensingWeather satellite images and derived productsWeather satellite images and derived productsVisible and infra-red images for cloud type and height, sea surface temperature, ocean Visible and infra-red images for cloud type and height, sea surface temperature, ocean

currents available real timecurrents available real timeDerived products: wind, wave, current etc very useful (particularly over sea areas) Derived products: wind, wave, current etc very useful (particularly over sea areas) Coverage and speed of delivery needs improving for some productsCoverage and speed of delivery needs improving for some products


Pseudo Colour ImagePseudo Colour Image

Resolution ~1 - Resolution ~1 - 3km/pixel3km/pixel

Images up to every Images up to every 15 minutes15 minutes

White – high cloud; White – high cloud; yellow – low cloudyellow – low cloud

Can show sea breeze Can show sea breeze front on higher res front on higher res imagesimages


SmartMet Satellite ImagesSmartMet Satellite ImagesSatellite image overlaid with forecast isobars and wind arrows


Sea Surface TemperatureSea Surface Temperature Needs no clouds!Needs no clouds! Land/sea temperatures Land/sea temperatures

can help predict sea and can help predict sea and land breezesland breezes

Gulf Stream & other Gulf Stream & other currentscurrents

Fish finding e.g. on Fish finding e.g. on fronts of temperature fronts of temperature changeschanges


Wind Speed and DirectionWind Speed and Direction- QuickScat and Ascat- QuickScat and Ascat

Satellites each pass Satellites each pass twice dailytwice daily

Data 1-2 hours old when Data 1-2 hours old when processed (or longer processed (or longer depending on source)depending on source)

25km resolution over 25km resolution over open water onlyopen water only

Wind direction can be 90 Wind direction can be 90 deg out occasionallydeg out occasionally

Can show local Can show local behaviours not shown by behaviours not shown by forecastsforecasts


Wind Speed and DirectionWind Speed and Direction- QuickScat and Ascat- QuickScat and Ascat


Digital AtmosphereDigital Atmosphere

Software for downloading, decoding and viewing current Software for downloading, decoding and viewing current

weather reportsweather reports

Also displays GRIB filesAlso displays GRIB files

A huge variety of data is available, but some of it is too A huge variety of data is available, but some of it is too

technical for the average sailortechnical for the average sailor

Simple and easy to useSimple and easy to use

Not as much data for Europe as for USA, due to different Not as much data for Europe as for USA, due to different

government policiesgovernment policies

Cost from US$89 for the software, downloads free dataCost from US$89 for the software, downloads free data


Digital AtmosphereDigital Atmosphere


Numerical ForecastsNumerical Forecasts All forecasts based on numerical modelsAll forecasts based on numerical models Manual forecaster input only useful for first 1-Manual forecaster input only useful for first 1-

2 days2 days Synoptic models for global weather forecasts Synoptic models for global weather forecasts

(e.g. GFS, WW3, ECMWF)(e.g. GFS, WW3, ECMWF) Mesoscale models for higher resolution local Mesoscale models for higher resolution local

forecasts (e.g. ETA, Theyr, HIRLAM, MM5). forecasts (e.g. ETA, Theyr, HIRLAM, MM5). These can better model fronts, sea breezes, These can better model fronts, sea breezes, mountain winds etcmountain winds etc


Forecast LimitationsForecast Limitations The smallest feature in the forecast is about 4x The smallest feature in the forecast is about 4x

the grid size, so a 0.5the grid size, so a 0.5° forecast doesn’t know ° forecast doesn’t know about most of the Channelabout most of the Channel

High Res forecasts from Theyr, ProGRIB, Moving High Res forecasts from Theyr, ProGRIB, Moving Weather, WindGuru, Kona all use GFS model as Weather, WindGuru, Kona all use GFS model as the starting point, with no extra met data input, the starting point, with no extra met data input, so are often no better than the GFS model so are often no better than the GFS model (though sometimes they are)(though sometimes they are)

Beware of sites and software that just Beware of sites and software that just interpolate to get a higher resolution, e.g. interpolate to get a higher resolution, e.g. Moving Weather, or web sites giving forecasts Moving Weather, or web sites giving forecasts for “your location”, e.g. BBCfor “your location”, e.g. BBC


Weather MapsWeather Maps

Many sites have weather maps for viewingMany sites have weather maps for viewing Typically generated automatically from Typically generated automatically from

numerical modelsnumerical models Sites may use the same data source but just Sites may use the same data source but just

presented differentlypresented differently Images can be large, so slow to downloadImages can be large, so slow to download Viewing relatively inflexibleViewing relatively inflexible


Weather Map SitesWeather Map Sites

Westwind – Westwind – www.westwind.chwww.westwind.ch - - searchable database of all European searchable database of all European datadata

Theyr – high resolution forecasts – Theyr – high resolution forecasts – www.theyr.netwww.theyr.net or www.theyr.tv or www.theyr.tv


Westwind ExampleWestwind Example


Met OfficeMet Office


GRIB FilesGRIB Files

Standard file format displayed by many chart plottersStandard file format displayed by many chart plotters

Download numerical data – faster than imagesDownload numerical data – faster than images

Free data: 1 or 0.5 degree, 3 or 6 hour resolution of wind, Free data: 1 or 0.5 degree, 3 or 6 hour resolution of wind,

pressure etc, all repackaged from standard US sourcespressure etc, all repackaged from standard US sources

Use tools like Saildocs or download from sites like RaymarineUse tools like Saildocs or download from sites like Raymarine

Higher resolution data at a charge e.g. Meteo France NaviMail, Higher resolution data at a charge e.g. Meteo France NaviMail,

ProGribProGrib

Each file is standalone, so cannot combine downloadsEach file is standalone, so cannot combine downloads


Free GRIB File SourcesFree GRIB File Sources

Raytech – www.raymarine.com (3 day Raytech – www.raymarine.com (3 day fcsts)fcsts)

Navcenter.com – Navcenter.com – www.navcenter.com/newdwnld.ccmlwww.navcenter.com/newdwnld.ccml

Global Marine Net – Global Marine Net – www.globalmarinenet.net/grib.htmwww.globalmarinenet.net/grib.htm (5 (5 day fcsts)day fcsts)

Saildocs – Saildocs – www.saildocs.comwww.saildocs.com - e-mail - e-mail serviceservice


GRIB FilesGRIB Files


Moving WeatherMoving Weather

Uses standard GFS data, but interpolates to make it Uses standard GFS data, but interpolates to make it

seem betterseem better


Good for overview or long passages, but not detailed Good for overview or long passages, but not detailed

enough for coastal sailingenough for coastal sailing

Cost £25 for the software, and £125/year for the Cost £25 for the software, and £125/year for the

forecastsforecasts


UGribUGrib

Uses standard GFS data for wind, rain and Uses standard GFS data for wind, rain and

pressurepressure


Uses discrete GRIB filesUses discrete GRIB files

Free of charge (at the moment!)Free of charge (at the moment!)


SmartMetSmartMet Combines forecasts, satellite imagery, current Combines forecasts, satellite imagery, current

weather reports – widest range of data of any weather reports – widest range of data of any software in its classsoftware in its class

Small, fast downloads – smaller than GRIBSmall, fast downloads – smaller than GRIB Integrated database, no problems of separate Integrated database, no problems of separate

filesfiles GRIB import and exportGRIB import and export Subscription £49/yearSubscription £49/year


Chart Plotters with GRIBChart Plotters with GRIB

seaPro – GRIB viewer and routingseaPro – GRIB viewer and routing Maxsea – GRIB downloads, viewer and Maxsea – GRIB downloads, viewer and

optional routingoptional routing Raytech – GRIB downloads, viewer and Raytech – GRIB downloads, viewer and

routingrouting Nobeltec – GRIB downloads and viewerNobeltec – GRIB downloads and viewer


Weather RoutingWeather Routing

Calculating the quickest route to sailCalculating the quickest route to sailInputs:Inputs:- Your boat’s polarsYour boat’s polars- Tidal streams / ocean currentsTidal streams / ocean currents- Forecast winds (GRIB file)Forecast winds (GRIB file)Outputs:Outputs:- Optimal routeOptimal route- IsochronesIsochronesPrograms: Maxsea, seaPro, Raytech, DeckmanPrograms: Maxsea, seaPro, Raytech, Deckman


Maxsea RoutingMaxsea Routing


ConclusionsConclusions Huge amounts of data out thereHuge amounts of data out there Research the data that meets your needs before going afloatResearch the data that meets your needs before going afloat Trade-off of cost of data against level of detail, reliability and comms costsTrade-off of cost of data against level of detail, reliability and comms costs Always compare the forecast with what you observe!Always compare the forecast with what you observe!

Met Data via the Internet Tim Thornton. November 2007 Smartcom Software Ltd Why use the Internet?...

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Transcript of Met Data via the Internet Tim Thornton. November 2007 Smartcom Software Ltd Why use the Internet?...