Issyk-Kul Sentinel-2 cal/val survey

More than 4,000 chlorophyll-a and 1,000 suspended-sediment observations from Issyk-Kul lidar transects, used in regional Sentinel-2 models

Published figures

Interpolated campaign fields, reproduced in their original published form.

Whole-lake composite

Interpolated chlorophyll a field mapped along the lidar track, Lake Issyk-Kul, Whole-lake composite
Fig. 1Chlorophyll a
Interpolated total organic carbon field mapped along the lidar track, Lake Issyk-Kul, Whole-lake composite
Fig. 2Total organic carbon
Interpolated total suspended matter field mapped along the lidar track, Lake Issyk-Kul, Whole-lake composite
Fig. 3Total suspended matter

2016 campaign

Interpolated chlorophyll a field mapped along the lidar track, Lake Issyk-Kul, 2016 campaign
Fig. 4Chlorophyll a
Interpolated total organic carbon field mapped along the lidar track, Lake Issyk-Kul, 2016 campaign
Fig. 5Total organic carbon
Interpolated total suspended matter field mapped along the lidar track, Lake Issyk-Kul, 2016 campaign
Fig. 6Total suspended matter

Eastern basin, July 2022

Interpolated chlorophyll a field mapped along the lidar track, Lake Issyk-Kul, Eastern basin, July 2022
Fig. 7Chlorophyll a
Interpolated CDOM field mapped along the lidar track, Lake Issyk-Kul, Eastern basin, July 2022
Fig. 8CDOM
Interpolated total suspended matter field mapped along the lidar track, Lake Issyk-Kul, Eastern basin, July 2022
Fig. 9TSM

Northern shore, July 2022

Interpolated chlorophyll a field mapped along the lidar track, Lake Issyk-Kul, Northern shore, July 2022
Fig. 10Chlorophyll a
Interpolated CDOM field mapped along the lidar track, Lake Issyk-Kul, Northern shore, July 2022
Fig. 11CDOM
Interpolated total suspended matter field mapped along the lidar track, Lake Issyk-Kul, Northern shore, July 2022
Fig. 12TSM
Lake Issyk-KulCentral Asia
10 km
● Lake Issyk-Kul 2016, 2016-10-31 – 2016-11-03181,188 measurements IDW interpolation, 600 samples
Chl-a0.030.17µg/L
CDOM2.197.11a.u.
TSM0.320.84mg/L

Fig. 13 Campaign measurement record. 181,188 lidar returns are plotted along the vessel track for Chl-a, CDOM, TSM. The field view applies inverse-distance weighting to the same observations; the shoreline is from Natural Earth.

Issyk-Kul is a large, deep, oligotrophic lake in the Kyrgyz mountains. During a one-day survey, LIF lidar transects produced more than 4,000 chlorophyll-a observations and 1,000 measurements of suspended sediment in the upper water layer.

The survey was timed to a satellite overpass. Its in-situ record was used to develop preliminary regional bio-optical models and evaluate them against Sentinel-2A imagery. The results were published in Remote Sensing in 2023.