Colored dissolved organic matter (CDOM) absorbance from lagoon, ocean, and river sites along the Alaska Beaufort Sea coast, 2021-ongoing

Multiple water types (river, lagoon, ocean) from the North Slope of Alaska and nearshore Beaufort Sea are sampled seasonally by the Beaufort Lagoon Ecosystems LTER (BLE LTER) Core Program to investigate biogeochemical linkages between terrestrial, lagoon, and open ocean ecosystems. Water samples from multiple depths are collected during full ice cover (April), ice break-up (mid-June to early July), and open water (late July and August) periods, filtered, and analyzed for light absorption spectra within 24 hours of collection. Wavelength-specific light absorption coefficients are reported between 200 and 600 nanometers. The data is organized in "long" or "tidy" format, with columns of station, date, wavelength, and absorption. Please see included MakeColumnsAsWavelengths.R, MakeColumnsAsDates.R, and ReshapeDataInExcel.txt for some common ways to reorganize the table for further CDOM analysis. In 2022, data from 2019 were removed due to quality issues (please see revision 1 of this dataset for 2019 CDOM values). For users who may have used 2019 data from this dataset, there are additional files to inform decisions going forward. "BLE_LTER_CDOM_2019_sample_flags.csv" lists which 2019 samples are entirely unreliable, versus usable with caution. "BLE_LTER_CDOM_2021_blank_mean_sd_absorptions.csv" lists mean and standard deviations at each wavelength from all blanks taken in 2021; this is meant to give info on the instruments used and will not be updated further. Please see the methods section for more information on 2019 data.

博福特泻湖生态系统长期生态研究（Beaufort Lagoon Ecosystems LTER，缩写BLE LTER）核心项目开展季节性采样，采集对象为阿拉斯加北坡及博福特海近岸区域的多种水体类型（河流、泻湖、海洋），旨在探究陆地、泻湖与开阔海洋生态系统之间的生物地球化学联系。
研究团队在全冰期（4月）、融冰期（6月中旬至7月初）以及开阔水域期（7月下旬至8月）采集不同深度的水样，经过滤后于采样后24小时内进行光吸收光谱分析。本数据集报告了200至600纳米波段范围内的波长特异性光吸收系数。
该数据集采用“长格式（long format）”或“整洁格式（tidy format）”进行组织，包含站位、日期、波长和吸光度四列字段。如需了解用于进一步开展有色溶解有机物（Colored Dissolved Organic Matter, CDOM）分析的表格重组常用方法，请参阅附带的`MakeColumnsAsWavelengths.R`、`MakeColumnsAsDates.R`以及`ReshapeDataInExcel.txt`文件。
2022年，由于质量问题，2019年的数据集已被移除（如需查看2019年CDOM数据，请参阅本数据集的修订版1）。对于曾使用本数据集2019年数据的用户，我们提供了额外文件以辅助其后续决策。`BLE_LTER_CDOM_2019_sample_flags.csv`文件列出了2019年所有不可靠的水样，以及可谨慎使用的水样。`BLE_LTER_CDOM_2021_blank_mean_sd_absorptions.csv`文件列出了2021年所有空白对照样在各波长下的吸光度均值与标准差；该文件用于提供所用仪器的相关信息，且不会再进行更新。如需了解2019年数据的更多详情，请参阅方法部分。