Subsea permafrost carbon stocks and climate change sensitivity estimated by expert assessment
Abstrak
The continental shelves of the Arctic Ocean and surrounding seas contain large stocks of organic matter (OM) and methane (CH _4 ), representing a potential ecosystem feedback to climate change not included in international climate agreements. We performed a structured expert assessment with 25 permafrost researchers to combine quantitative estimates of the stocks and sensitivity of organic carbon in the subsea permafrost domain (i.e. unglaciated portions of the continental shelves exposed during the last glacial period). Experts estimated that the subsea permafrost domain contains ∼560 gigatons carbon (GtC; 170–740, 90% confidence interval) in OM and 45 GtC (10–110) in CH _4 . Current fluxes of CH _4 and carbon dioxide (CO _2 ) to the water column were estimated at 18 (2–34) and 38 (13–110) megatons C yr ^−1 , respectively. Under Representative Concentration Pathway (RCP) RCP8.5, the subsea permafrost domain could release 43 Gt CO _2 -equivalent (CO _2 e) by 2100 (14–110) and 190 Gt CO _2 e by 2300 (45–590), with ∼30% fewer emissions under RCP2.6. The range of uncertainty demonstrates a serious knowledge gap but provides initial estimates of the magnitude and timing of the subsea permafrost climate feedback.
Topik & Kata Kunci
Penulis (32)
Sayedeh Sara Sayedi
Benjamin W Abbott
Brett F Thornton
Jennifer M Frederick
Jorien E Vonk
Paul Overduin
Christina Schädel
Edward A G Schuur
Annie Bourbonnais
Nikita Demidov
Anatoly Gavrilov
Shengping He
Gustaf Hugelius
Martin Jakobsson
Miriam C Jones
DongJoo Joung
Gleb Kraev
Robie W Macdonald
A David McGuire
Cuicui Mu
Matt O’Regan
Kathryn M Schreiner
Christian Stranne
Elena Pizhankova
Alexander Vasiliev
Sebastian Westermann
Jay P Zarnetske
Tingjun Zhang
Mehran Ghandehari
Sarah Baeumler
Brian C Brown
Rebecca J Frei
Akses Cepat
- Tahun Terbit
- 2020
- Sumber Database
- DOAJ
- DOI
- 10.1088/1748-9326/abcc29
- Akses
- Open Access ✓