Abbreviations

Abbreviation	Definition	Additional information
AVHRR	Advanced Very-High-Resolution Radiometer	Thermal instrument onboard NOAA’s POES and European MetOp satellites (1 km).
BC	Brockmann Consult GmbH	One of the partner companies of Syke, which specialises in Earth Observation solutions.
BEAM	BEAM software	The software used to process satellite images. No longer in use; replaced by the SNAP software.
C2RCC	Case 2 Regional Coast Colour	A joint atmospheric correction and bio-optical inversion model which can interpret, e.g., the concentrations of chlorophyll-a, suspended solids, and CDOM from a satellite image.
C2R	Case 2 Regional	A model family including, e.g., the atmospheric correction and bio-optical inversion models C2RCC, C2X, and C2X-COMPLEX. Can also refer to C2RCC’s earliest development versions.
C2X	Case 2 Extreme	A combined atmospheric correction and bio-optical inversion model developed specifically to operate in extreme aquatic environments, such as areas with high levels of CDOM content.
CDOM	Humic substances or Colored dissolved organic matter	Dissolved organic molecules (humic and fulvic acids) that make water appear as brownish. The amound of CDOM is usually expressed as the absorption coefficient of the filtrate at 400 nm (unit 1/m). Note that the Finnish standard differs here from international conventions, where the reference wavelength is typically 440 nm.
Chl-a	Chlorophyll-a concentration	Photosynthetic and light-harvesting pigment that occurs in all photosynthesizing organisms. The amount of Chl-a is usually expressed as the concentration of the pigment (unit μg/L or mg/m³).
EO	Earth Observation	The usage of remote sensing technologies (satellites) to monitor land, marine and atmosphere. In a wide sense, this term includes also the supporting ground data collection.
ESA	European Space Agency
FSC	Fractional Snow Cover	As a percentage of the forest floor (0 % – 100 %).
FUB-CSIRO	Free University of Berlin & Commonwealth Scientific and Industrial Research Organisation	A combined atmospheric correction and bio-optical inversion model which can be used to interpret, e.g., the absorption of chlorophyll-a, suspended solids, and CDOM. Named after the research institutes where the model was developed. Used in Syke for chlorophyll-a interpretation from Envisat MERIS and Sentinel-3 OLCI.
HR	High Resolution	High spatial resolution (In Tarkka-service 10 m – 30 m).
Idepix	multi-sensor pixel identification tool	A cloud detection tool commonly used for identifying cloudy areas by various satellite instruments.
LC8/9	Landsat-8/9	NASA and USGS’s newest-generation Landsat satellites which include OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor) instruments, with a spatial resolution ranging from 30 meters to 100 meters.
LIE	Lake Ice Extent	The occurrence of lake ice is reported on a nominal scale that may include information about the presence of snow cover on ice.
MERIS	MEdium Resolution Imaging Spectrometer	The mid-resolution instrument of the ESA Envisat satellite series (up to 2012).
MODIS	MOderate Resolution Imaging Spectrometer	The mid-resolution instrument of NASA’s Terra and Aqua satellites.
MR	Medium Resolution	Medium spatial resolution (In Tarkka-service 300 m – 1 km).
MS	Monitoring Station	Stations from which in-situ observations are made.
MSFD	Marine Strategy Framework Directive	Directive `2008/56/EC` of the European Parliament and of the Council establishing a framework for community action in the field of marine environmental policy.
MSI	MultiSpectral Instrument	The high-resolution instrument of the Copernicus program’s S2 satellite series, with a resolution ranging from 10 meters to 60 meters.
NASA	National Aeronautics and Space Administration	The United States’ space agency.
OLCI	Ocean and Land Colour Instrument	The optical mid-resolution instrument of the Sentinel-3 satellite series has a resolution of 300 meters.
OLI	Operational Land Imager	The optical instrument of the Landsat satellite series.
RGB	Red Green Blue	A color model based on the red, green, and blue primary colours, which is founded on the perception of colour by the human eye.What is a true-color image
SDT	Secchi Disk Transparency	The depth to which a white Secchi disk with a 30-cm diameter may be submerged so that it is still just visible. Unit metres.
SLSTR	The Sea and Land Surface Temperature Radiometer	The thermal instrument of the Sentinel-3 satellite series (1 km).
SNAP	Sentinel Application Platform	A ESA software that brings together tools for processing satellite images.
SST	Sea surface temperature	Unit °C (centigrade) or K (kelvin).
S2	Sentinel-2	The satellite series of the Copernicus program with the high-resolution instrument MSI (10 m – 60 m).
S3	Sentinel-3	The satellite series of the Copernicus program with the medium-resolution instruments OLCI and SLSTR (300 m – 1 km).
TIRS	Thermal Infrared Sensor	The thermal instrument of the Landsat satellite series (100 m).
TURB	Turbidity	Represents how strongly the water scatters light. Unit FNU (nephelometric turbidity unit) or FTU (formazin turbidity unit), which mean the same thing.
WFD	Water Framework Directive	Directive `2000/60/EC` of the European Parliament and of the Council establishing a framework for Community action in the field of water policy. In Tarkka service it refers to the monitoring areas (water bodies) defined based on the directive in Finland or in other countries.