Validation of MERIS products for Skagerrak and Norwegian coastal waters

Transcription

1 Validation of MERIS products for Skagerrak and Norwegian coastal waters Kai Sørensen (NIVA), Are Folkestad (NIVA) Kerstin Stelzer (BC), Carsten Brockmann (BC) Roland Doerffer (GKSS)

2 Outline of the presentation Validation and monitoring activities in Skagerrak Validation of L2 algal concentration and TSM Standard IPF products FUB (1.1), ICOL (1.0.2) and Case2R (1.3 and 1.4. beta) product Monthly control of L3 product using Ferrybox data Importance of coastal products for monitoring and Water Framework Directive

3 Validation and monitoring in Norwegian waters Objective of the validation activities: Validation of the L2 products Match-up data for the reprocessing Objective for the monitoring activities Implement remote sensing products into the monitoring activities (Water Directive) Use of data from the Ferrybox network for validation and monitoring

4 Ferrybox network in North Sea /Kattegat and Norwegian waters Water intake 4 meters depth Water sampling unit for TSM, Chl-a (HPLC), apig and BPA Sensor for Chl-a fluorescence as proxy for Chl-a Turbidity as proxy for TSM Salinity and temperature Sensor at deck for Ed, Ld and Lu measurements for reflectance calculation (on some of the ships) Skin temperature using SISTeR in periods on one ship (Tim Nightingale, RAL)

5 The NRT data are available on for a first control

6 Ferrybox transect of suspended material in Skagerrak 17. March 2007 TSM_Ferrybox=0.955*Turb (Sørensen et.al. FerryBox Deliverable D5-4) Suspended material (g/m TSM_Ferrybox IPF TSM C2R TSM FUB TSM Latitude

7 Ferrybox data for validation Ferrybox in water sensor and water samples give data from one depth (4m) only We must assume that this value are representative for the upper water column In Skagerrak 10-15% of the time the concentration at 4-5 m his higher than the surface Sensor data like turbidity and Chl-a fluorescence must be transferred to be used as proxy for TSM and Chl-a Water samples can be used for determination of TSM, Chl-a_HPLC, apig and BPA following the protocols Calculations of reflectance from Ferrybox radiometers (TriOS, Ramses) are under investigation

8 Algal_2 (IPF) versus Ferrybox sampled Chl-a (HPLC) for Ferrybox 2007 data. Timediff < 3 hours and lat>57.6 and lat< algal_ Chl2.hplc Coefficient of determination, R^2 algal_2 = * Chl-a R h Time difference between ship and satellite observation (h)

9 Algal_2 versus Chl-a HPLC in Skagerrak Ferrybox and match-up data 16 Timedifference < 3 hours and latitude > 57.6 N and latitude < 58.6 N algal_2 (mg/m3) algal_2 = * Chl-a_HPLC Chl-a_HPLC (mg/m3)

10 TSM versus suspended material in Skagerrak Ferrybox and match-up data 3.0 Timediff<3 and lat<58.6 and lat> total_suspended (g/m3) total_suspended = * TSM TSM (g/m3)

11 FUB Algal_2 versus Chl-a HPLC for Ferrybox sampled data - Skagerrak FUB Algal_2 (mg/m3) FUB Algal_2= x Chl-a R2 = Chl-a HPLC (mg/m3)

12 FUB and Case2R versus Chl-a HPLC in Skagerrak 17.March Chl.a HPLC (µg/l) FUB Chl C2R chlor Algal_2 (mg/m3) Latitude

13 MERIS L3 TSM and Ferrybox_TSM Mean September 2004 Problems in the fjords

14 MERIS L3 algal_2 and Ferrybox Chl-a (Chl-a fluor) Mean for July 2003 compared to class. system Moderate Good Very good Meget God God Moderat Dårlig Meget Dårlig <3,5 3,5-<7 7-<11 11-<20 >20

15 Better coastal products is needed for implementation in the Water Directive The Water Directive area for the Oslo fjord 1 nm mile from the coast (2 km) Good products for the coast and in the fjords are highly needed 59 N

16 Norway FR data for the Skagerrak and Kattegat Sweden Skagerrak MERIS FR C2R Chlorophyll June 6, 2008 Denmark Baltic Sea North Sea GKSS IFK Germany

17 MERIS FR - using ICOL and Case2R processors in the Oslo fjord Standard RR Case2 Chl-a FR Case2Regional Chl-a FR ICOL and C2R Chl-a

18 3 FUB and ICOL in the Oslofjord 31. March 2007 Algal concentration (mg Chl-a/m3) FUB RR algal_concentration Chl.a HPLC (µg/l) FUB FR algal_concentration FUB FR algal_concentration_icol 59 N Latitude

19 Summary The standard IPF algal_2 and TSM perform well in the open areas of Skagerrak The FUB algal_2 work well in the open areas The preliminary comparison with C2R processor (1.4 beta) show promising results for Chl-a ICOL in combination with Case2R and FUB improve the overall image and recover data in the fjord In the Oslo fjord the processors products fails concerning to retrieve the correct concentrations The L3 product of algal_2 and TSM give quantitatively good data for the open areas It is a urgent need to improve the coastal products to be able to implement such products in the Water Directive for Norwegian waters