• Economic losses of carbon emissions from circum-Arctic permafrost regions under RCP-SSP scenarios

      Chen, Yating; Liu, Aobo; Zhang, Zhihua; Hope, Chris; Crabbe, M. James C.; Beijing Normal University; Shandong University; Cambridge University; University of Oxford; University of Bedfordshire (Elsevier, 2018-12-20)
      Under rapid Arctic warming, the vast amount of labile organic carbon stored in Arctic permafrost soils poses a potentially huge threat. Thawing permafrost will release hundreds of billion tons of soil carbon into the atmosphere in the form of CO2 and CH4 that would further intensify global warming and bring more challenges to human society. In this study, we use the PInc-PanTher model to estimate carbon emissions from thawing permafrost in the circum-Arctic during 2010-2100 followed by the PAGE09 integrated assessment model to evaluate the net economic losses caused by these permafrost carbon emissions. Our results show that in terms of net present value (NPV), the release of CO2 and CH4 from circum-Arctic permafrost will generate estimated net economic losses of US$2.5 trillion (5-95% range: 0.3-11.2 US$ trillion) under the RCP4.5-SPP1 scenario and US$12.7 trillion (5-95% range: 1.6-41.8 US$ trillion) under the RCP8.5-SPP3 scenario between 2010-2100, which contribute ~4.9% and ~6.4% respectively of net economic losses of global carbon emissions.
    • Extreme climate response to marine cloud brightening in the arid Sahara-Sahel-Arabian Peninsula zone

      Zhu, Yuanzhuo; Zhang, Zhihua; Crabbe, M. James C.; Shandong University; Beijing Normal University; Oxford University; University of Bedfordshire; Shanxi University (Emerald, 2021-02-08)
      Purpose Climatic extreme events are predicted to occur more frequently and intensely and will significantly threat the living of residents in arid and semi-arid regions. Therefore, this study aims to assess climatic extremes’ response to the emerging climate change mitigation strategy using a marine cloud brightening (MCB) scheme. Design/methodology/approach Based on Hadley Centre Global Environmental Model version 2-Earth System model simulations of a MCB scheme, this study used six climatic extreme indices [i.e. the hottest days (TXx), the coolest nights (TNn), the warm spell duration (WSDI), the cold spell duration (CSDI), the consecutive dry days (CDD) and wettest consecutive five days (RX5day)] to analyze spatiotemporal evolution of climate extreme events in the arid Sahara-Sahel-Arabian Peninsula Zone with and without MCB implementation. Findings Compared with a Representative Concentration Pathways 4.5 scenario, from 2030 to 2059, implementation of MCB is predicted to decrease the mean annual TXx and TNn indices by 0.4–1.7 and 0.3–2.1°C, respectively, for most of the Sahara-Sahel-Arabian Peninsula zone. It would also shorten the mean annual WSDI index by 118–183 days and the mean annual CSDI index by only 1–3 days, especially in the southern Sahara-Sahel-Arabian Peninsula zone. In terms of extreme precipitation, MCB could also decrease the mean annual CDD index by 5–25 days in the whole Sahara and Sahel belt and increase the mean annual RX5day index by approximately 10 mm in the east part of the Sahel belt during 2030–2059. Originality/value The results provide the first insights into the impacts of MCB on extreme climate in the arid Sahara-Sahel-Arabian Peninsula zone.