Temperature thresholds and time slices


Here are some thoughts on how ISIMIP2b simulations can be analysed to address different scientific questions involving global-mean temperature thresholds. You are invited to comment and add to these notes, which are intended to assist the entire ISIMIP community, whilst not being prescriptive. The precise nature of the scientific question will determine the appropriate method for handling thresholds.

The plots show: (upper row) annual global mean tas; (middle row) 31-year running mean of global mean tas; (lower row) 31-year running mean of global mean tas minus 1661-1860 global mean piControl tas. Each column depicts a different global climate model and the colours represent the pre-industrial (grey), historical (black), RCP2.6 (blue), RCP4.5 (green), RCP6.0 (yellow), and RCP8.5 (red) scenarios. All of these plots are based on bias-corrected tas values.

ISIMIP2bext_runningmean.svg

Below are tables of the year in which the (bias-corrected) 31-year running mean of global mean temperature crosses the given thresholds.

RCP2.6

GMT-threshold IPSL-CM5A-LR GFDL-ESM2M MIROC5 HadGEM2-ES
3.0° - - - -
2.5° - - - -
2.0° 2029 - - -
1.5° 2009 - 2048 2026
1.0° 1993 2014 2015 2012
0.5° 1961 1989 1996 2000

RCP4.5

GMT-threshold IPSL-CM5A-LR GFDL-ESM2M MIROC5 HadGEM2-ES
3.0° 2066 - - -
2.5° 2044 - - 2062
2.0° 2029 - 2069 2046
1.5° 2011 2049 2039 2031
1.0° 1993 2014 2017 2015
0.5° 1961 1989 1995 2000

RCP6.0

GMT-threshold IPSL-CM5A-LR GFDL-ESM2M MIROC5 HadGEM2-ES
3.0° 2068 - - 2076
2.5° 2048 - - 2063
2.0° 2029 2076 2071 2050
1.5° 2010 2056 2052 2032
1.0° 1993 2016 2023 2014
0.5° 1961 1989 1996 1999

RCP8.5

GMT-threshold IPSL-CM5A-LR GFDL-ESM2M MIROC5 HadGEM2-ES
3.0° 2046 2082 2071 2056
2.5° 2036 2068 2060 2047
2.0° 2024 2053 2048 2037
1.5° 2009 2036 2033 2025
1.0° 1993 2014 2014 2012
0.5° 1961 1989 1995 2000