Dataset extent
NÄKÖSYVYYS (VELMU)
Data and Resources
Additional Info
Field | Value |
---|---|
File Identifier | {811B434E-75A1-4F53-9445-A4B4BDADA499} |
Metadata Language | fin |
Organisation responsible for metadata | Suomen ympäristökeskus |
Contact information of the organisation responsible for metadata | gistuki@syke.fi |
The role of the organisation responsible for metadata | pointOfContact |
Metadata revision date | 2024-01-23 |
EPSG Code of the Reference System, see https://epsg.io/ | EPSG:3067 |
Resource Date | 2015-09-01 |
Resource Date Type | publication |
Unique Resource identifier | |
Organisation Responsible for Resource | Suomen ympäristökeskus |
Contact information of the organisation responsible for Resource | syke.velmudata@syke.fi |
The role of the organisation responsible for Resource | originator |
INSPIRE Data Theme | Sea regions |
GEMET Concepts Keyword | remote sensing |
GEMET Concepts Keyword | marine environment |
Resource Classification | Paikkatietoaineisto |
Other keywords | Ei-Inspire |
Other keywords: Thesaurus name | |
Other keywords | itämeri.fi |
Other keywords: Thesaurus name | |
Other keywords | Veden ominaisuudet |
Other keywords: Thesaurus name | |
Other keywords | FEO |
Other keywords: Thesaurus name | |
Other keywords | Velmu |
Other keywords: Thesaurus name | |
Use constraints and source | Creative Commons Nimeä 4.0 Kansainvälinen http://www.syke.fi/fi-FI/Avoin_tieto/Kayttolupa_ja_vastuut Lähde: Lappalainen, J., Virtanen, E. A., Kallio, K., Junttila, S., & Viitasalo, M. (2019). Substrate limitation of a habitat-forming genus Fucus under different water clarity scenarios in the northern Baltic Sea. Estuarine, Coastal and Shelf Science, 218, 31-38. doi: https://doi.org/10.1016/j.ecss.2018.11.010 |
Access Constraints | no limitations |
Representation Type | grid |
Scale (Denominator) | 400000 |
Scale (Denominator) | 4000000 |
Resource Language | fin |
Resource Topic Category | environment |
Service Type | |
Begin Date of Temporal Extent | unknown |
End Date of Temporal Extent | unknown |
Lineage Information | Näkösyvyyden laskentaan käytettiin MERIS (Medium Resolution Imaging Spectrometer) satelliittisensorin täyden resoluution kuvia (erotuskyky 300 m, kolmas uudelleen prosessointi). Mukaan valittiin pilvettömät ja osittain pilvettömät MERIS-kuvat touko-syyskuun ajalta vuosilta 2003–2011. Humuspitoisuuden mittana käytettiin humuksen absorptionkerrointa (1/m) aallonpituudella 400 nm. Humusta ei tulkittu satelliittikuvilta, vaan laskennassa käytettiin keskimääräistä rannikon seuranta-asemien tuloksiin (PIVET tietokanta, 2003-2011) ja r/v Arandalla tehtyihin mittauksiin perustuvaa humuskarttaa. Calculation of secchi depth was based on optical models with concentrations of total suspended solids, chlorophyll-a and humic substances as well as sun altitude angle and specific inherent absorption and scattering coefficients as input. In addition, the models require diffuse downwelling attenuation coefficient (Kd), which is calculated as an intermediate product. The calculation of secchi depth was based on full resolution (300 m, 3rd re-processing) images of MERIS (Medium Resolution Imaging Spectrometer) satellite sensor (Medium Resolution Imaging Spectrometer). All cloudless or nearly cloudless images were processed from June-August in 2003-2011. The measure of humic substance concentration was absorption coefficient (1/m) of a filtered sample at 400 nm. Humic substance concentration was not estimated from satellite images. Instead, a map of average humic substance concentrations was used as input to the optical models. This map was based on routine in situ measurements at coastal monitoring stations in 2003-2011 (data obtained from PIVET database of Environmental administration in Finland) and on measurements onboard r/v Aranda (Pasi Ylöstalo, unpublished data). För beräkningen av siktdjup användes MERIS (Medium Resolution Imaging Spectrometer) satellitsensorns fullresolutionsbilder (kan urskilja med en noggrannhet av 300 m). Bilderna som användes var från dagar med inga eller lite moln från maj-september månaderna, åren 2003-2011. För beräkningen av humushalter användes humusens absorptionskoefficient (1/m) med våglängden 400 nm. Humushalterna tolkades inte med satellitbilder, utan med medeltal från uppföljningsstationer vid kusten (PIVET databas, 2003-2011) och en humuskarta gjord med mätningsresultat från R/V Aranda. |