Water-Column Studies near a Melting Arctic Iceberg

Glacial icebergs contain large amounts of nitrate, an important phytoplankton nutrient. Low density iceberg meltwater, in rising, mixes with euphotic zone water nearby, wherein NO3 is in low concentration. Rising meltwater may also entrain nutrient-rich deeper waters and raise them to sunlit depths....

Full description

Bibliographic Details
Main Author: Shulenberger,Eric
Other Authors: SAN DIEGO NATURAL HISTORY MUSEUM CA
Format: Text
Language:English
Published: 1981
Subjects:
Biology
Snow
Ice and Permafrost
*WATER
*ANTARCTIC REGIONS
*PLANTS(BOTANY)
*GLACIERS
*GREENLAND
*ICEBERGS
DENSITY
RATES
DIRECTION FINDING
NUTRIENTS
PROFILES
FEASIBILITY STUDIES
VERTICAL ORIENTATION
MELTING
WIND DIRECTION
MIXING
LOW DENSITY
PHYTOPLANKTON
SUNLIGHT
CHLOROPHYLLS
EUPHOTIC ZONES
Glacial icebergs
Water column studies
Plant biology
Antarctic
Arctic
Greenland
Antarc*
Ice
Iceberg*
permafrost
Phytoplankton
Online Access:http://www.dtic.mil/docs/citations/ADA108304
http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA108304
Description
Summary:Glacial icebergs contain large amounts of nitrate, an important phytoplankton nutrient. Low density iceberg meltwater, in rising, mixes with euphotic zone water nearby, wherein NO3 is in low concentration. Rising meltwater may also entrain nutrient-rich deeper waters and raise them to sunlit depths. Sixteen vertical profiles of nutrients (PO4, NO3, SiO2), chlorophyll-a, and physical parameters were taken near a Greenland iceberg at approx. 50 deg. N, 50 deg. W in May-June 1980. Chlorophyll profiles show very pronounced maxima at or just below the maximum rate of change of water density vs. depth; profile forms are heterogeneous (no 'typical' form is evident). No enhancement of chlorophyll concentration was found re distance from or direction to the iceberg. Effects of mixing on NO 3 concentrations are marginally detectable, but no 'wake' or 'downwind' effects were observed. The iceberg does not appear to grossly perturb water column plant biology nearby, but measures of rates of productivity might show otherwise, particularly near larger (e.g. Antarctic) icebergs. (Author)

Similar Items