Colored dissolved organic matter of Lena River water from 11.04.2019 (#79) to 11.09.2019 (#201)

• Main Authors: Juhls, Bennet, Overduin, Pier Paul, Morgenstern, Anne, Chetverova, Antonina, Hölemann, Jens A
• Format: Dataset
• Language: English
• Published: PANGAEA
• Subjects: Absorption coefficient; colored dissolved organic matter at 200 nm; colored dissolved organic matter at 201 nm; colored dissolved organic matter at 202 nm; colored dissolved organic matter at 203 nm; colored dissolved organic matter at 204 nm; colored dissolved organic matter at 205 nm; colored dissolved organic matter at 206 nm; colored dissolved organic matter at 207 nm; colored dissolved organic matter at 208 nm; colored dissolved organic matter at 209 nm; colored dissolved organic matter at 210 nm; colored dissolved organic matter at 211 nm; colored dissolved organic matter at 212 nm; colored dissolved organic matter at 213 nm; colored dissolved organic matter at 214 nm; colored dissolved organic matter at 215 nm; colored dissolved organic matter at 216 nm; colored dissolved organic matter at 217 nm; colored dissolved organic matter at 218 nm; colored dissolved organic matter at 219 nm; colored dissolved organic matter at 220 nm; colored dissolved organic matter at 221 nm; colored dissolved organic matter at 222 nm; colored dissolved organic matter at 223 nm; colored dissolved organic matter at 224 nm; lena river
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.967404

We collected water samples from the river surface in the center of the Olenekskaya Channel near Samoylov Island using a pre-rinsed HDPE 1 L bottle. During the open water period (June to October), water was sampled from a small boat, and during ice-covered period (November to May), through a hole drilled through the river ice. Some samples during the river ice break-up (between May and June) as well as some samples during the ice freeze-up in October were taken from the shore due to the inaccessibility of a more centered location on the river channel. For CDOM absorption (aCDOM(λ)), the sample was filtered through a 0.45 μm cellulose acetate filter which had been rinsed with 20 mL sample water. CDOM samples were collected in pre-rinsed 50 or 100 mL amber glass bottles that were stored in the dark at 4°C until analysis. aCDOM was measured at the Otto Schmidt Laboratory for Polar and Marine Research (OSL), Saint Petersburg, Russia using a SPECORD 200 spectrophotometer (Analytik Jena). The absorbance (A) was measured between 200 and 750 nm in 1 nm steps using a 1, 2 or 5 cm cuvette, depending on the expected concentration of dissolved organic matter. Absorption (a) was calculated from the resulting absorbance measurements via aCDOM(λ) = 2.303 * A(λ) * l, where l is the path length (length of cuvette in meter). Every 5 to 10 samples, the reference sample (Milli-Q water) was exchanged and a blank was measured to avoid instrument drift.