Articles | Volume 13, issue 1
Biogeosciences, 13, 223–238, 2016
Biogeosciences, 13, 223–238, 2016

Research article 15 Jan 2016

Research article | 15 Jan 2016

The carbon cycle in Mexico: past, present and future of C stocks and fluxes

G. Murray-Tortarolo1, P. Friedlingstein1, S. Sitch2, V. J. Jaramillo3, F. Murguía-Flores4, A. Anav1, Y. Liu5, A. Arneth6, A. Arvanitis6, A. Harper1, A. Jain7, E. Kato8, C. Koven9, B. Poulter10, B. D. Stocker11, A. Wiltshire12, S. Zaehle13, and N. Zeng14 G. Murray-Tortarolo et al.
  • 1College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK
  • 2College of Life and Environmental Sciences, University of Exeter, Exeter, UK
  • 3Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Mexico
  • 4School of Geographical Sciences, University of Bristol, Bristol, UK
  • 5Climate Change Research Centre, University of New South Wales, Sydney, Australia
  • 6Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
  • 7Department of Atmospheric Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
  • 8Global Environment Program, Research & Development Division, The Institute of Applied Energy, Tokyo, Japan
  • 9Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
  • 10Institute on Ecosystems and the Department of Ecology, Montana State University, Bozeman, Montana, USA
  • 11Department of Life Sciences, Imperial College, London, UK
  • 12Met Office Hadley Centre, Exeter, UK
  • 13Biogeochemical Intergration Department, Max Planck Institute for Biogeochemistry, Jena, Germany
  • 14Department of Atmospheric and Oceanic Science and Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA

Abstract. We modeled the carbon (C) cycle in Mexico with a process-based approach. We used different available products (satellite data, field measurements, models and flux towers) to estimate C stocks and fluxes in the country at three different time frames: present (defined as the period 2000–2005), the past century (1901–2000) and the remainder of this century (2010–2100). Our estimate of the gross primary productivity (GPP) for the country was 2137 ± 1023 TgC yr−1 and a total C stock of 34 506 ± 7483 TgC, with 20 347 ± 4622 TgC in vegetation and 14 159 ± 3861 in the soil.

Contrary to other current estimates for recent decades, our results showed that Mexico was a C sink over the period 1990–2009 (+31 TgC yr−1) and that C accumulation over the last century amounted to 1210 ± 1040 TgC. We attributed this sink to the CO2 fertilization effect on GPP, which led to an increase of 3408 ± 1060 TgC, while both climate and land use reduced the country C stocks by −458 ± 1001 and −1740 ± 878 TgC, respectively. Under different future scenarios, the C sink will likely continue over the 21st century, with decreasing C uptake as the climate forcing becomes more extreme. Our work provides valuable insights on relevant driving processes of the C cycle such as the role of drought in drylands (e.g., grasslands and shrublands) and the impact of climate change on the mean residence time of soil C in tropical ecosystems.

Short summary
We modelled the carbon (C) cycle in Mexico for three different time periods: past (20th century), present (2000-2005) and future (2006-2100). We used different available products to estimate C stocks and fluxes in the country. Contrary to other current estimates, our results showed that Mexico was a C sink and this is likely to continue in the next century (unless the most extreme climate-change scenarios are reached).
Final-revised paper