Publication Date:
2024-02-15
Description:
Vertical profiles of downwelling irradiance (Ed) and upwelling radiance (Lu) were measured during legs 2, 3, and 4 using a Compact-Optical Profiling System (C-OPS) in an ICE-Pro frame from Biospherical Instruments, Inc. (for a detailed description see Morrow et al. 2010 (see further details)). Additionally, above-surface incident downward irradiance (Es(0+)) was measured at about two meters above sea level and was used to correct in-water Ed and Lu for changes in the incident light field during Lu profiling (Zibordi et al., 2019; doi:10.25607/OBP-691). All radiometric quantities were measured at 19 wavelengths spanning from 380 to 875 nm. In-water profiles were obtained from the boat using a 3 m long pole, deployed towards the sun to avoid shading from the boat. The data that were acquired with a tilt of more than 5 degrees were discarded (Hooker et al., 2013; doi:10.5194/bg-10-4511-2013). Due to the high absorption and scattering coefficients in the sampled waters and considering relatively large dimensions of the ICE-Pro, self-shading correction was not negligible. Absorption observed in the present study were mostly outside the limits examined by Gordon and Ding (1992; doi:10.4319/lo.1992.37.3.0491), suggesting the application of the correction questionable. To overcome this issue, we performed Monte-Carlo simulations using the SimulO software (Leymarie et al., 2010; doi:10.1364/AO.49.005415) for examining the self-shading correction factor on Lu at null depth (Gerbi et al., 2016 (doi:10.1175/JTECH-D-16-0067.1); Leymarie et al., 2018 (doi:10.3389/fmars.2018.00437)). The exact dimensions of the ICE-Pro were simulated and virtually placed at a depth of 0.5 m. A wide range of IOPs was considered to cover the conditions encountered in the field. The simulations provide a robust relationship between the computed self-shading and the quantity x = a + bb, where a is the total measured absorption coefficient (i.e., the contributions of pure water, CDOM, algal and non-algal particles) and bb is the total backscattering coefficient (i.e., the contributions of water molecules and particles). The shade-corrected upwelling radiance (Lu corrected) can be expressed as a function of the measured radiance (Lu measured) as: (1) L_u(corrected)=(L_u(measured))/((1-ε)), (2) ε=1-e^(-0.14*(a+bb)), where (2) is fitted for solar zenith angles 〉 45° and bb (which was not measured in the field) was calculated using an empirical relationship from the Malina-cruise dataset (Doxaran et al., 2012 (doi:10.5194/bg-9-3213-2012); Massicotte et al., 2020 (doi:10.5194/essd-13-1561-2021)). Subsurface downward irradiance and upward radiance Ed(0-) and Lu(0-) were estimated with an iterative linear fitting of the log-transformed Ed(z) and Lu(z) vs depth z. Fitting was applied to successively greater depths until the correlation coefficient (r2) exceeded 0.99 or until the layer thickness reached 2.5 m (Bélanger et al., 2017; doi:10.1175/JTECH-D-16-0176.1). Remote Sensing Reflectance (Rrs) was calculated following Mobley (1999; doi:10.1364/AO.38.007442) with: Rrs(λ)=(0.54*L_u (0^-,λ))/(E_s(0^+,λ)). To calculate the Rrs we used the R "Cops" package (https://github.com/belasi01/Cops) (Bélanger 2017: doi:10.1175/JTECH-D-16-0176.1).
Keywords:
1_STN01; 1_STN020; 1_STN040; 1_STN0a; 1_STN0b; 1_STN140alt; 1_STN150alt; 1_STN340alt; 1_STN350; 1_STN360; 1_STN370alt; 1_STN380alt; 1_STN540alt; 1_STN550; 1_STN740; 1_STN810; 1_STN830; 1_STN840; 1_STN850; 1_STN860; 1_STN870; 2_STN030; 2_STN040; 2_STN1030; 2_STN1040; 2_STN1050; 2_STN1060; 2_STN110; 2_STN120; 2_STN140alt; 2_STN150alt; 2_STN310; 2_STN320; 2_STN330; 2_STN340alt; 2_STN350; 2_STN360; 2_STN370; 2_STN380alt_2; 2_STN420; 2_STN430; 2_STN450; 2_STN530; 2_STN540alt; 2_STN550; 2_STN565; 2_STN620; 2_STN630; 2_STN740; 2_STN800; 2_STN810; 2_STN820; 2_STN830; 2_STN840; 2_STN850; 2_STN860; 2_STN870; 2_STN999; 2_STNxxx; 2_XX2; 2_XX3; 3_STN010; 3_STN020; 3_STN030; 3_STN040; 3_STN1030; 3_STN1040; 3_STN1050; 3_STN1060; 3_STN125; 3_STN130; 3_STN130_5m; 3_STN135; 3_STN140alt; 3_STN150alt; 3_STN330; 3_STN340alt; 3_STN350; 3_STN360; 3_STN370alt; 3_STN380; 3_STN740; 3_STN800; 3_STN810; 3_STN820; 3_STN830; 3_STN840; 3_STN850; 3_STN860; 3_STN870; 3_STNR01; 3_STNR02; 3_STNR02_5m; 3_STNR03; 3_STNR04; 3_STNR05; 3_STNR06; 3_STNR07; 3_STNR08; 3_STNR09; 3_STNR09_20m; 3_STNR10; 3_STNR11; 3_STNR12; 3_STNR13; 3_STNxxx; 4_STN010; 4_STN020; 4_STN030; 4_STN040; 4_STN1030; 4_STN1040; 4_STN1050; 4_STN120; 4_STN125; 4_STN130; 4_STN135; 4_STN140alt; 4_STN140alt_2; 4_STN150alt; 4_STN330; 4_STN340alt; 4_STN350; 4_STN360; 4_STN370; 4_STN380alt; 4_STN740; 4_STN800; 4_STN810; 4_STN820; 4_STN830; 4_STN840; 4_STN840_2; 4_STN850; 4_STN860; 4_STN870; 4_STNR01; 4_STNR03; 4_STNR04; 4_STNR05; 4_STNR08; 4_STNR09; 4_STNR12; 4_STNXX4; 4_STNXX4_2; biogeochemistry; Biooptics; Coastal waters; Compact-Optical Profiling System (C-OPS), ICE-Pro frame (Biospherical Instruments, Inc.); Cruise/expedition; DATE/TIME; Event label; hydrographic data; LATITUDE; LONGITUDE; Mackenzie; Mackenzie Delta, Canada; MULT; Multiple investigations; NUNATARYUK; NUNATARYUK, Permafrost thaw and the changing Arctic coast, science for socioeconomic adaptation; NunaWP4Mackenzie19_1_STN01; NunaWP4Mackenzie19_1_STN020; NunaWP4Mackenzie19_1_STN040; NunaWP4Mackenzie19_1_STN0a; NunaWP4Mackenzie19_1_STN0b; NunaWP4Mackenzie19_1_STN140alt; NunaWP4Mackenzie19_1_STN150alt; NunaWP4Mackenzie19_1_STN340alt; NunaWP4Mackenzie19_1_STN350; NunaWP4Mackenzie19_1_STN360; NunaWP4Mackenzie19_1_STN370alt; NunaWP4Mackenzie19_1_STN380alt; NunaWP4Mackenzie19_1_STN540alt; NunaWP4Mackenzie19_1_STN550; NunaWP4Mackenzie19_1_STN740; NunaWP4Mackenzie19_1_STN810; NunaWP4Mackenzie19_1_STN830; NunaWP4Mackenzie19_1_STN840; NunaWP4Mackenzie19_1_STN850; NunaWP4Mackenzie19_1_STN860; NunaWP4Mackenzie19_1_STN870; NunaWP4Mackenzie19_2_STN030; NunaWP4Mackenzie19_2_STN040; NunaWP4Mackenzie19_2_STN1030; NunaWP4Mackenzie19_2_STN1040; NunaWP4Mackenzie19_2_STN1050; NunaWP4Mackenzie19_2_STN1060; NunaWP4Mackenzie19_2_STN110; NunaWP4Mackenzie19_2_STN120; NunaWP4Mackenzie19_2_STN140alt; NunaWP4Mackenzie19_2_STN150alt; NunaWP4Mackenzie19_2_STN310; NunaWP4Mackenzie19_2_STN320; NunaWP4Mackenzie19_2_STN330; NunaWP4Mackenzie19_2_STN340alt; NunaWP4Mackenzie19_2_STN350; NunaWP4Mackenzie19_2_STN360; NunaWP4Mackenzie19_2_STN370; NunaWP4Mackenzie19_2_STN380alt_2; NunaWP4Mackenzie19_2_STN420; NunaWP4Mackenzie19_2_STN430; NunaWP4Mackenzie19_2_STN450; NunaWP4Mackenzie19_2_STN530; NunaWP4Mackenzie19_2_STN540alt; NunaWP4Mackenzie19_2_STN550; NunaWP4Mackenzie19_2_STN565; NunaWP4Mackenzie19_2_STN620; NunaWP4Mackenzie19_2_STN630; NunaWP4Mackenzie19_2_STN740; NunaWP4Mackenzie19_2_STN800; NunaWP4Mackenzie19_2_STN810; NunaWP4Mackenzie19_2_STN820; NunaWP4Mackenzie19_2_STN830; NunaWP4Mackenzie19_2_STN840; NunaWP4Mackenzie19_2_STN850; NunaWP4Mackenzie19_2_STN860; NunaWP4Mackenzie19_2_STN870; NunaWP4Mackenzie19_2_STN999; NunaWP4Mackenzie19_2_STNxxx; NunaWP4Mackenzie19_2_XX2; NunaWP4Mackenzie19_2_XX3; NunaWP4Mackenzie19_3_STN010; NunaWP4Mackenzie19_3_STN020; NunaWP4Mackenzie19_3_STN030; NunaWP4Mackenzie19_3_STN040; NunaWP4Mackenzie19_3_STN1030; NunaWP4Mackenzie19_3_STN1040; NunaWP4Mackenzie19_3_STN1050; NunaWP4Mackenzie19_3_STN1060; NunaWP4Mackenzie19_3_STN125; NunaWP4Mackenzie19_3_STN130; NunaWP4Mackenzie19_3_STN130_5m; NunaWP4Mackenzie19_3_STN135; NunaWP4Mackenzie19_3_STN140alt; NunaWP4Mackenzie19_3_STN150alt; NunaWP4Mackenzie19_3_STN330; NunaWP4Mackenzie19_3_STN340alt; NunaWP4Mackenzie19_3_STN350; NunaWP4Mackenzie19_3_STN360; NunaWP4Mackenzie19_3_STN370alt; NunaWP4Mackenzie19_3_STN380; NunaWP4Mackenzie19_3_STN740; NunaWP4Mackenzie19_3_STN800; NunaWP4Mackenzie19_3_STN810; NunaWP4Mackenzie19_3_STN820; NunaWP4Mackenzie19_3_STN830; NunaWP4Mackenzie19_3_STN840; NunaWP4Mackenzie19_3_STN850; NunaWP4Mackenzie19_3_STN860; NunaWP4Mackenzie19_3_STN870; NunaWP4Mackenzie19_3_STNR01; NunaWP4Mackenzie19_3_STNR02; NunaWP4Mackenzie19_3_STNR02_5m; NunaWP4Mackenzie19_3_STNR03; NunaWP4Mackenzie19_3_STNR04; NunaWP4Mackenzie19_3_STNR05; NunaWP4Mackenzie19_3_STNR06; NunaWP4Mackenzie19_3_STNR07; NunaWP4Mackenzie19_3_STNR08; NunaWP4Mackenzie19_3_STNR09; NunaWP4Mackenzie19_3_STNR09_20m; NunaWP4Mackenzie19_3_STNR10; NunaWP4Mackenzie19_3_STNR11; NunaWP4Mackenzie19_3_STNR12; NunaWP4Mackenzie19_3_STNR13; NunaWP4Mackenzie19_3_STNxxx; NunaWP4Mackenzie19_4_STN010; NunaWP4Mackenzie19_4_STN020; NunaWP4Mackenzie19_4_STN030; NunaWP4Mackenzie19_4_STN040; NunaWP4Mackenzie19_4_STN1030; NunaWP4Mackenzie19_4_STN1040; NunaWP4Mackenzie19_4_STN1050; NunaWP4Mackenzie19_4_STN120; NunaWP4Mackenzie19_4_STN125; NunaWP4Mackenzie19_4_STN130; NunaWP4Mackenzie19_4_STN135; NunaWP4Mackenzie19_4_STN140alt; NunaWP4Mackenzie19_4_STN140alt_2; NunaWP4Mackenzie19_4_STN150alt; NunaWP4Mackenzie19_4_STN330; NunaWP4Mackenzie19_4_STN340alt; NunaWP4Mackenzie19_4_STN350; NunaWP4Mackenzie19_4_STN360; NunaWP4Mackenzie19_4_STN370; NunaWP4Mackenzie19_4_STN380alt; NunaWP4Mackenzie19_4_STN740; NunaWP4Mackenzie19_4_STN800; NunaWP4Mackenzie19_4_STN810; NunaWP4Mackenzie19_4_STN820; NunaWP4Mackenzie19_4_STN830; NunaWP4Mackenzie19_4_STN840; NunaWP4Mackenzie19_4_STN840_2; NunaWP4Mackenzie19_4_STN850; NunaWP4Mackenzie19_4_STN860; NunaWP4Mackenzie19_4_STN870; NunaWP4Mackenzie19_4_STNR01; NunaWP4Mackenzie19_4_STNR03; NunaWP4Mackenzie19_4_STNR04; NunaWP4Mackenzie19_4_STNR05; NunaWP4Mackenzie19_4_STNR08; NunaWP4Mackenzie19_4_STNR09; NunaWP4Mackenzie19_4_STNR12; NunaWP4Mackenzie19_4_STNXX4; NunaWP4Mackenzie19_4_STNXX4_2; Remote sensing reflectance at 395 nm; Remote sensing reflectance at 412 nm; Remote sensing reflectance at 443 nm; Remote sensing reflectance at 490 nm; Remote sensing reflectance at 510 nm; Remote sensing reflectance at 560 nm; Remote sensing reflectance at 665 nm; Remote sensing reflectance at 683 nm; Remote sensing reflectance at 710 nm; Remote sensing reflectance at 765 nm; Remote sensing reflectance at 778 nm; Remote sensing reflectance at 865 nm; Station label
Type:
Dataset
Format:
text/tab-separated-values, 856 data points
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