The outcome of the pilot will be a dedicated web service providing:

• Monthly 90-day seasonal ensemble forecasts of streamflow and hydropower reservoir inflow at end-user (Kemijoki Oy) selected forecast points. A particular focus will be placed on snowmelt driven runoff forecasting.
• Daily 10-day deterministic forecasts (incl. nowcasts and hindcasts) of streamflow and hydropower reservoir inflow at end-user (Kemijoki Oy) selected forecast points. In addition to streamflow forecasts, the service will provide maps of numerous other key hydrological variables used in Hydropower production optimization and general water management operations.
• A unified web service combining data from various other external sources in a single user interface allowing the user to assess forecasts uncertainties by comparing information derived from an FMI hydrological model (HOPS) with external observations and estimates – a particular focus will be placed on providing EO-based observations and in situ measurements of snow conditions and soil freeze/thaw states.

An alpha version: is already running on hops.fmi.fi

• Most of the planned products will be added by the end of November 2020
• Seasonal forecasts will be added during December 2020.

A beta version is expected to be completed by the end of December 2020

• The service will be tested together with the end user during January and May 2021.

Following user feedback and service accuracy assessments a first published version is expected to be finalized by June-July 2021

• Further additions and changes to the web service are still unknown and to be determined

Availability: public

• 20-day hindcast maps
• 10-day forecast maps
• Hindcast and deterministic forecast time series plots
• 90-day ensemble forecast time series and probabilistic output

The back-end of the operational web service will be run on WEkEO DIAS and will be considered as the production server. A copy of the back-end will (and does) exist on an FMI internal development server. The front-end web service will be on an FMI server (hops.fmi.fi).

Web based application

In most basins in Scandinavia and Finland, more than 50 % of the annual precipitation falls as snow. Errors in snowmelt timing and melt rate simulations are one of the largest sources of stream flow prediction errors in snowmelt-dominated watersheds. Thus snow storage and melting periods have a significant impact on hydropower production reservoirs. Forecasts of reservoir inflow and energy prices are used to schedule the quantity and timing of releases for daily, weekly, and seasonal operations. Ingestion of Earth Observation (EO) based snow observations can significantly reduce hydrological model snowpack simulation uncertainties.

• Decreasing the vulnerability of energy companies to variations in meteorological and hydrological conditions through improved seasonal forecast products is the main expected impact of the project.
• The methodology for determining snow conditions using coarse resolution EO data (for hydropower optimization) is already available. The main objective is to derive higher resolution and higher quality products, using Sentinel-1/-2/-3 data, to improve timeliness and information content.
• End-user tailored products on hydrological conditions will be disseminated to the key end user; Kemijoki Oy. A particular focus will be placed on snow reservoir energy potential. The key diagnostics are reservoir inflow and snow reservoir energy potential, which together with other factors is a measure of stored hydropower potential.
• EO based snow water equivalents will be used to assess model forecast uncertainties

All data provided by the web service will be made available for download through the web service.

The source code can be made available on GitHub after the service is finalized (this still needs to be discussed internally at FMI). 

If the pilot is deemed of interest for the GEO/GEOSS catalogue, registration will be established, especially in connection with Finnish portals. This will be assessed after full launch of the service, during the Summer of 2021.