Extreme summer melt: Assessing the habitability and physical structure of rotting first-year Arctic sea ice. Chukchi Sea, Alaska. 2015-2018

• Main Authors: Junge, Karen, Light, Bonnie, Orellana, Monica, Frantz, Carie
• Format: Dataset
• Language: English
• Published: Arctic Data Center 2017
• Subjects: sea ice, Arctic, ice melt, sea ice polymers, sea ice bacteria, algae, polymers; Barrow, Alaska; Chukchi Sea, Xray computed tomography; Arctic; Chukchi Sea; Rotten; Barrow; Chukchi; Extreme summer melt: Assessing the habitability and physical structure of rotting first-year Arctic sea ice; ice core; Sea ice; Alaska
• Online Access: https://dx.doi.org/10.18739/a29g5gd58; https://arcticdata.io/catalog/#view/doi:10.18739/A29G5GD58

The response of Arctic sea ice to a warming climate includes decreases in extent, lower ice concentration, and reduced ice thickness. Summer melt seasons are lengthening with earlier melt onsets and later autumn freezeups. We believe this will likely lead to an increase in so-called "rotten ice" in the Arctic at the end of summer. This ice has experienced a long summer of melt, is fragile, difficult to work with, and has received little attention. Comprehensive information on its physical and microbiological properties does not exist. This data set was generated to address two main objectives: determination of the physical and microbial characteristics and the microstructural evolution of sea ice exposed to severe melt. This research developed and applied state-of-the-art microbiological, molecular, biogeochemical and geophysical techniques to examine the character and evolution of natural Arctic sea ice at the end of the melt season at field sites near Barrow, Alaska. This project assessed: - ice physical characteristics (ice density, salinity, light scattering coefficients, and microstructure) using microscopy and X-ray computed tomography techniques - ice algal and bacterial characteristics (abundance, biomass, and diversity) using epifluorescence microscopy, flow cytometry and Illumina sequencing techniques - polymer gel characteristics (abundance, gel carbon biomass, and size) using flow cytometry. CT scans of the collected ice core samples are included in zip file format. Each file contains several hundred images of a specific sample. More information about each sample can be found in "CT_Core_Metadata.xlsx" and "CT_Core_Metadata_reformatted.csv".