Editing IPCC:AR6/SR15/Chapter-3 (section)

==== 3.3.3.1 Observed and attributed changes in regional precipitation ====

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Observed global changes in the water cycle, including precipitation, are more uncertain than observed changes in temperature (Hartmann et al., 2013; Stocker et al., 2013) <sup>[[#fn:r95|95]]</sup> . There is ''high confidence'' that mean precipitation over the mid-latitude land areas of the Northern Hemisphere has increased since 1951 (Hartmann et al., 2013) <sup>[[#fn:r96|96]]</sup> . For other latitudinal zones, area-averaged long-term positive or negative trends have ''low confidence'' because of poor data quality, incomplete data or disagreement amongst available estimates (Hartmann et al., 2013) <sup>[[#fn:r97|97]]</sup> . There is, in particular, ''low confidence'' regarding observed trends in precipitation in monsoon regions, according to the SREX report (Seneviratne et al., 2012) <sup>[[#fn:r98|98]]</sup> and AR5 (Hartmann et al., 2013) <sup>[[#fn:r99|99]]</sup> , as well as more recent publications (Singh et al., 2014; Taylor et al., 2017; Bichet and Diedhiou, 2018; <sup>[[#fn:r100|100]]</sup> see Supplementary Material 3.SM.2).

For heavy precipitation, AR5 (Hartmann et al., 2013) <sup>[[#fn:r101|101]]</sup> assessed that observed trends displayed more areas with increases than decreases in the frequency, intensity and/or amount of heavy precipitation ( ''likely'' ). In addition, for land regions where observational coverage is sufficient for evaluation, it was assessed that there is ''medium confidence'' that anthropogenic forcing has contributed to a global-scale intensification of heavy precipitation over the second half of the 20th century (Bindoff et al., 2013a) <sup>[[#fn:r102|102]]</sup> .

Regarding changes in precipitation associated with global warming of 0.5°C, the observed record suggests that increases in precipitation extremes can be identified for annual maximum 1-day precipitation (RX1day) and consecutive 5-day precipitation (RX5day) for GMST changes of this magnitude (Supplementary Material 3.SM.2, Figure 3.SM.7; Schleussner et al., 2017) <sup>[[#fn:r103|103]]</sup> . It should be noted that assessments of attributed changes in the IPCC SREX and AR5 reports were generally provided since 1950, for time frames also approximately corresponding to a 0.5°C global warming (3.SM).

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