Climate Dynamics

, Volume 38, Issue 7, pp 1489–1500

The potential of vegetation feedback to alleviate climate aridity over the United States associated with a 2×CO2 climate condition

  • Chang-Eui Park
  • Chang-Hoi Ho
  • Su-Jong Jeong
  • Jinwon Kim
  • Song Feng
Article

DOI: 10.1007/s00382-011-1150-x

Cite this article as:
Park, CE., Ho, CH., Jeong, SJ. et al. Clim Dyn (2012) 38: 1489. doi:10.1007/s00382-011-1150-x

Abstract

This study examines the potential impact of vegetation feedback on changes in summer climate aridity over the contiguous United States (US) due to the doubling of atmospheric CO2 concentration using a set of 100-year-long climate simulations made by a global climate model interactively coupled with a dynamic vegetation model. The Thornthwaite moisture index (Im), which quantifies climate aridity on the basis of atmospheric water supply (i.e., precipitation) and atmospheric water demand (i.e., potential evapotranspiration, PET), is used to measure climate aridity. Warmer atmosphere and drier surface resulting from increased CO2 concentration increase climate aridity over most of the contiguous US. This phenomenon is due to larger increments in PET than in precipitation, regardless of the presence or absence of vegetation feedback. Compared to simulations without active dynamic vegetation feedback, the presence of vegetation feedback significantly alleviates the increase in aridity. This vegetation-feedback effect is most noticeable in the subhumid regions such as southern, midwestern and northwestern US, primarily by the increasing vegetation greenness. In these regions, the greening in response to warmer temperatures enhances moisture transfer from soil to atmosphere by evapotranspiration (ET). The increased ET and subsequent moistening over land areas result in weaker surface warming (1–2 K) and PET (3–10 mm month−1), and greater precipitation (4–10 mm month−1). Collectively, they result in moderate increases in Im. Our results suggest that moistening by enhanced vegetation feedback may prevent aridification under climatic warming especially in areas vulnerable to climate change, with consequent implications for mitigation strategies.

Keywords

Vegetation feedbackClimate aridityThornthwaite moisture indexDynamic vegetation modelClimate changeGlobal warmingUnited States

Supplementary material

382_2011_1150_MOESM1_ESM.docx (929 kb)
Supplementary material 1 (DOCX 928 kb)

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Chang-Eui Park
    • 1
  • Chang-Hoi Ho
    • 1
  • Su-Jong Jeong
    • 1
    • 4
  • Jinwon Kim
    • 2
  • Song Feng
    • 3
  1. 1.School of Earth and Environmental Sciences, Climate Physics LaboratorySeoul National UniversitySeoulKorea
  2. 2.Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesUSA
  3. 3.School of Natural ResourcesUniversity of Nebraska-LincolnLincolnUSA
  4. 4.Princeton UniversityPrincetonUSA