Simple Feature data model in Finnish Meteorological Institute's … · 2017-10-11 · FMI Open Data Portal follows INSPIRE requirements. FMI Open Data Portal Meta data Services The

Simple Feature data model in Finnish Meteorological Institute's INSPIRE

download service

Mikko Visa, Roope Tervo

• Finnish Meteorological Institute opened its data in 2013.• Most data sets that FMI has property rights to were opened.

• Both (near) real-time and historical and climatological data.• Still more datasets to be opened

• Data is provided freely in machine readable format.

15.9.2017 2

FMI Open Data

https://en.ilmatieteenlaitos.fi/open-data

Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo

9/15/2017 INSPIRE Compliant Weather Data | Roope Tervo, Mikko Visa, Jukka Pakarinen 3

FMI Open DataDatasets

• Way beyond INSPIRE Data Specification scope• Instantaneous weather and marine observations

• AWS, soundings, mast, air quality, sun radiation, marine, lightning…

• Radiation observations by Radiation and Nuclear Safety Authority (STUK)

• Road weather observations• Model data from 6 different weather and marine models• Weather radar images• Climatological data

• Observation time series, analysis, climatological reference…

FMI Open Data Portal follows INSPIRE requirements.

FMI Open Data Portal

Meta data Services

The very same data portal works as Open Data and INSPIRE portal.

15.9.2017 4

ISO19115 WFS WMSCSW

Grid SeriesObservations

Time SeriesObservations

Data Models O&M

SimpleFeature

GRIBNetCDF GeoTIFF

Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo

Download Service (WFS 2.0)

• Web Feature Service (WFS) 2.0 Simple Profile

• Based on stored queries• Predefined data sets with

possibility for additional parameters (i.e. time and area)

• In-house production• Part of SmartMet Server (Open

Source)15.9.2017 5Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo

Data Modelso Observations and point

forecasts as GMLo The same data is published in:

o Grid Series Observationo Point Time Series

Observationo Simple Feature

o Gridded data is provided in appropriate binary format (GRIB, NetCDF, GeoTIFF…)

o WFS members contains the metadata ‘envelope’ with a link to actual data

15.9.2017 6Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo

Data Modelsgmlcov:MultiPointCoverage(Grid Series Observation)

9/15/2017 7

gml:rangeSetgml:doubleOrNilReasonTupleList

The data is listed for every point defined in domain set.

gml:domainSetgmlcov:simpleMultiPoint

The coverage is defined as a list of

points in 4 dimensional grid (lat,

lon, height, time).

gmlcov:rangeType

The parameters listed in range set

are defined in separate element.

FMI Open Meteorological Data Services | Roope Tervo

9/15/2017 8FMI Open Meteorological Data Services | Roope Tervo

Cons- Not intuitive- No natural

structure of XML XSLT and Xpath don’t work

Pros+ Compact+ Efficient+ Small file size+ Works for many

data types

9/15/2017 9

Data Modelsgmlcov:MultiPointCoverage


Data Modelswml2:MeasurementTimeseries(Point Time Series Observation)

9/15/2017 10

wml2:MeasurementTimeseries

One member contains time series of one parameter and

one location


9/15/2017 11FMI Open Meteorological Data Services | Roope Tervo

Cons- Lots of repetition- Large file size- Heavy for DOM-

based parsers- Don’t work e.g. for

lightning strikes

Pros+ Intuitive+ Easy to use+ XSLT & XPath

works

9/15/2017 12

Data Modelswml2:MeasurementTimeseries


Data ModelsSimple Feature

9/15/2017 13

Simple Feature

One member contains one time step of one parameter

and one location


Cons- Huge file size- Heavy for DOM-

based parsersPros+ Intuitive+ Easy to use+ Wide application

support

9/15/2017 14

Data ModelsSimple Feature


9/15/2017 15

Data Models file size comparison

81.7

52.9

1.81.3 1.2 0.20

102030405060708090

Document Size[MB]

CompressedDocumentSize[MB]


Timelineo Since 2013/06

o Grid Series Observation (multipointcoverage)o Point Time Series Observation (timeseries)o GeoTIFF/NetCDF/GRIB

o Since 2015/02o Simple Feature (simple)o At that time there was need to use WFS as an input

Store for serving WMS layers via Geoservero Geoserver was extended to support WFS 2.0 Stores via

Simple Feature


15.9.2017 Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo 17

15.9.2017 Open Data @ Finnish Meteorological Institute | Mikko Visa, Roope Tervo 18

And a little over830 000 data downloads

per day(9,6 req/s)

At the moment about 11 700

registered users

Some Experiences


Practicallyno clientsupportscomplexfeatures

Although standards are followed, there’s

a gap between provided data model

and clients’ capabilities

Some Experiences


Industry ishappy to usestandardized

services

Amateur andfreelance coders

would prefer simple JSON API

Some Experiences


So far maybeeven more

professionalinterest than

private

Quite many expected a user

interface to load data to i.e. to Excel

instead of machine readable interface

Some Experiences


Conclusionso No clear trends in Simple Feature usage

o Grid Series and Point Time Series have “kept their positions” apparently and especially within heavy users

o We believe Simple Feature is still a good complement to the two other data models and will be providing new data sets in Simple Feature as well

o Weather model and observation data is complex multidimensional, high volume and fast changing data

o Limits on how much simplification can be done


www.fmi.fi

http://www.slideshare.net/tervo/https://en.ilmatieteenlaitos.fi/open-data

Documents

Simple Feature data model in Finnish Meteorological Institute's … · 2017-10-11 · FMI Open Data Portal follows INSPIRE requirements. FMI Open Data Portal Meta data Services The