CaltechAUTHORS
  A Caltech Library Service

Changes in the surface energy budget after fire in boreal ecosystems of interior Alaska: An annual perspective

Liu, Heping and Randerson, James T. and Lindfors, Jamie and Chapin, F. Stuart, III (2005) Changes in the surface energy budget after fire in boreal ecosystems of interior Alaska: An annual perspective. Journal of Geophysical Research. Atmospheres, 110 (D13). Art. No. D13101. ISSN 2169-897X. doi:10.1029/2004jd005158. https://resolver.caltech.edu/CaltechAUTHORS:20181128-140625630

[img] PDF - Published Version
See Usage Policy.

816kB
[img] Plain Text (Tab‐delimited Table 1) - Supplemental Material
See Usage Policy.

1kB
[img] Plain Text (Tab‐delimited Table 2) - Supplemental Material
See Usage Policy.

780B
[img] Plain Text (Tab‐delimited Table 3) - Supplemental Material
See Usage Policy.

1kB
[img] Plain Text (Tab‐delimited Table 4) - Supplemental Material
See Usage Policy.

962B

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20181128-140625630

Abstract

Understanding links between the disturbance regime and regional climate in boreal regions requires observations of the surface energy budget from ecosystems in various stages of secondary succession. While several studies have characterized fire‐induced differences in surface energy fluxes from boreal ecosystems during summer months, much less is known about these differences over the full annual cycle. Here we measured components of the surface energy budget (including both radiative and turbulent fluxes) at three sites from a fire chronosequence in interior Alaska for a 1‐year period. Our sites consisted of large burn scars resulting from fires in 1999, 1987, and ∼1920 (hereinafter referred to as the 3‐, 15‐, and 80‐year sites, respectively). Vegetation cover consisted primarily of bunch grasses at the 3‐year site, aspen and willow at the 15‐year site, and black spruce at the 80‐year site. Annual net radiation declined by 31% (17 W m^(−2)) for both the 3‐ and the 15‐year sites as compared with the 80‐year site (which had an annual mean of 55 W m^(−2)). Annual sensible heat fluxes were reduced by an even greater amount, by 55% at the 3‐year site and by 52% at the 15‐year site as compared with the 80‐year site (which had an annual mean of 21 W m^(−2)). Absolute differences between the postfire ecosystems and the mature black spruce forest for both net radiation and sensible heat fluxes were greatest during spring (because of differences in snow cover and surface albedo), substantial during summer and winter, and relatively small during fall. Fire‐induced disturbance also initially reduced annual evapotranspiration (ET). Annual ET decreased by 33% (99 mm yr^(−1)) at the 3‐year site as compared with the 80‐year site (which had an annual flux of 301 mm yr^(−1)). Annual ET at the 15‐year site (283 mm yr^(−1)) was approximately the same as that from the 80‐year site, even though the 15‐year site had substantially higher ET during July. Our study suggests that differences in annual ET between deciduous and conifer stands may be smaller than that inferred solely from summer observations. This study provides a direct means to validate land surface processes in global climate models attempting to capture vegetation‐climate feedbacks in northern terrestrial regions.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.1029/2004jd005158DOIArticle
ORCID:
AuthorORCID
Randerson, James T.0000-0001-6559-7387
Additional Information:© 2005 by the American Geophysical Union. Received 23 June 2004; revised 28 January 2005; accepted 25 February 2005; published 1 July 2005. We thank M. Mack, E. A. G. Schuur, K. Treseder, and J. Harden for providing data on vegetation and soils at these sites and S. D. Chambers for providing invaluable insight about eddy covariance measurement techniques in boreal ecosystems. C. Dunn, J. Henkelman, and J. Smith contributed substantially to the development of these sites. J. Garron provided invaluable technical assistance throughout the year of this study. We are grateful for constructive suggestions and comments from three anonymous reviewers. This work was supported by an NSF RAISE grant OPP‐0097439, the Powell Foundation, and a gift from the Davidows to Caltech.
Funders:
Funding AgencyGrant Number
NSFOPP‐0097439
Powell FoundationUNSPECIFIED
Davidow Discovery FundUNSPECIFIED
Subject Keywords:boreal forest; eddy covariance; snow albedo; vegetation‐climate feedbacks; climate cooling
Issue or Number:D13
DOI:10.1029/2004jd005158
Record Number:CaltechAUTHORS:20181128-140625630
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20181128-140625630
Official Citation:Liu, H., J. T. Randerson, J. Lindfors, and F. S. Chapin III (2005), Changes in the surface energy budget after fire in boreal ecosystems of interior Alaska: An annual perspective, J. Geophys. Res., 110, D13101, doi: 10.1029/2004JD005158.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91309
Collection:CaltechAUTHORS
Deposited By: George Porter
Deposited On:28 Nov 2018 23:32
Last Modified:16 Nov 2021 03:40

Repository Staff Only: item control page