Lake-size dependency of wind shear and convection as controls on gas exchange
Files
(Published version)
Date
2012
Authors
Read, J.
Hamilton, D.
Desai, A.
Rose, K.
MacIntyre, S.
Lenters, J.
Smyth, R.
Hanson, P.
Cole, J.
Staehr, P.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Geophysical Research Letters, 2012; 39(9):1-5
Statement of Responsibility
Jordan S. Read, David P. Hamilton, Ankur R. Desai, Kevin C. Rose, Sally MacIntyre, John D. Lenters, Robyn L. Smyth, Paul C. Hanson, Jonathan J. Cole, Peter A. Staehr, James A. Rusak, Donald C. Pierson, Justin D. Brookes, Alo Laas, and Chin H. Wu
Conference Name
Abstract
<jats:p>High‐frequency physical observations from 40 temperate lakes were used to examine the relative contributions of wind shear (<jats:italic>u</jats:italic><jats:sub>*</jats:sub>) and convection (<jats:italic>w</jats:italic><jats:sub>*</jats:sub>) to turbulence in the surface mixed layer. Seasonal patterns of <jats:italic>u</jats:italic><jats:sub>*</jats:sub> and <jats:italic>w</jats:italic><jats:sub>*</jats:sub> were dissimilar; <jats:italic>u</jats:italic><jats:sub>*</jats:sub> was often highest in the spring, while <jats:italic>w</jats:italic><jats:sub>*</jats:sub>increased throughout the summer to a maximum in early fall. Convection was a larger mixed‐layer turbulence source than wind shear (<jats:italic>u</jats:italic><jats:sub>*</jats:sub>/<jats:italic>w</jats:italic><jats:sub>*</jats:sub> < 0.75) for 18 of the 40 lakes, including all 11 lakes <10 ha. As a consequence, the relative contribution of convection to the gas transfer velocity (<jats:italic>k</jats:italic>, estimated by the surface renewal model) was greater for small lakes. The average <jats:italic>k</jats:italic> was 0.54 m day<jats:sup>−1</jats:sup> for lakes <10 ha. Because <jats:italic>u</jats:italic><jats:sub>*</jats:sub> and <jats:italic>w</jats:italic><jats:sub>*</jats:sub>differ in temporal pattern and magnitude across lakes, both convection and wind shear should be considered in future formulations of lake‐air gas exchange, especially for small lakes.</jats:p>
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
Copyright 2012 by the American Geophysical Union.