Metadata:
Physical/chemical/biological sea ice characteristics in the Chukchi and Beaufort 
Sea in spring 2004

Author: Rolf Gradinger

Cruise: SBI Spring 2004 (HLY-04-02)

Grant Number: NSF 0125464

Overview

The data set consists of the sea ice measurements conducted at 10 stations between May 
21 and June 14 2004 including location, snow thickness, ice temperature, salinity, 
nutrients, chlorophyll a (chl a), and phaeopigments values. The data set for each station is 
presented on one separate worksheet within the file, which was produced with MS Excel 
X for MAC. All units for all parameters are provided within the spreadsheet.  Examples 
for the sampling equipment used can be found at: http://www.sfos.uaf.edu/research/seaicebiota/SBI2/index.html

Description of methodology applied

Ice cores were collected with a KOVACS-type ice auger (9 cm diameter). Ice temperature was 
measured in small drill holes at 5 to 10 cm intervals over the entire ice 
thickness with a Traceable thermometer (accuracy of 0.05 ¡K) immediately after 
coring.  The entire cores were sectioned in segments of variable lengths and completely 
melted directly in the dark for salinity, nutrient, and algal pigments. Chl a analysis 
was conducted fluorometrically after melt water was filtered through GF/F filters. 
Nutrient concentrations were measured onboard the HEALY by the SBI nutrient team. To 
avoid salinity effects in the nutrient determination, 10ml of melted ice core samples 
were mixed with 28ml of Sargasso Sea water with known nutrient concentrations as 
recommended by L. Codispoti. The final salinity in the mixed samples was always >25. The 
reported nutrient concentrations have been corrected for the dilution effect and 
represent the bulk concentration in the melted sea ice samples. PAR (photosynthetically active 
radiation, 400-700nm) intensity was measured with a LI-COR underwater 4d sensor, T and S 
below the ice was determined with an YSI85 sensor. Freezing of the T,S sensor head 
occurred at several locations. 

Point of contact:
Rolf Gradinger, School of Fisheries and Ocean Sciences, Univ. Alaska Fairbanks, 
rgradinger@ims.uaf.edu, (907) 474 7407