Accelerating net terrestrial carbon uptake during the warming hiatus due to reduced respiration

• DOI: 10.1038/nclimate3204
• Publication Date: 2017-01-23T18:03:03Z
• Authors: Ashley Ballantyne; William Smith; William Anderegg; Pekka Kauppi; Jorge Sarmiento; Pieter Tans; Elena Shevliakova; Yude Pan; Benjamin Poulter; Alessandro Anav; Pierre Friedlings...; Richard Houghton; Steven Running
• Keywords: Hiatus; Biome

The recent ‘warming hiatus’ presents an excellent opportunity to investigate climate sensitivity of carbon cycle processes. Here we combine satellite and atmospheric observations to show that the rate of net biome productivity (NBP) has significantly accelerated from −0.007 ± 0.065 PgC yr−2 over the warming period (1982 to 1998) to 0.119 ± 0.071 PgC yr−2 over the warming hiatus (1998–2012). This acceleration in NBP is not due to increased primary productivity, but rather reduced respiration that is correlated (r = 0.58; P = 0.0007) and sensitive (γ = 4.05 to 9.40 PgC yr−1 per °C) to land temperatures. Global land models do not fully capture this apparent reduced respiration over the warming hiatus; however, an empirical model including soil temperature and moisture observations better captures the reduced respiration. Satellite and atmospheric observations show that the rate of net biome productivity has accelerated over the warming ‘hiatus’ period (1998–2012). This net gain results from reduced respiration, rather than increased primary productivity.