Editing IPCC:AR6/WGI/Chapter-12 (section)

==== 12.4.3.4 Snow and Ice ====

<div id="h3-48-siblings" class="h3-siblings"></div>

'''Snow:''' The snow season length in Australia has decreased by 5% during 2000–2013 relative to 1954–1999, especially in spring ( [[#Pepler--2015|Pepler et al., 2015]] ). A shift in the date of peak snowfall has also been observed with an 11-day advance over the same period ( [[#Pepler--2015|Pepler et al., 2015]] ). A decreasing trend in maximum snow depth has been observed for Australian alpine regions since the late 1950s, with the largest declines during spring and at lower altitudes. Maximum snow depth is highly variable and is strongly influenced by rare heavy snowfall days, which have no observed trends in frequency (CSIRO and BOM, 2020).

Projections for Southern Australia and New Zealand show a continuing reduction in snowfall during the 21st century ( ''high confidence'' ). The magnitude of decrease varies with the altitude of the region and the emissions scenario. At elevations lower than 1500 m, years without snowfall are projected from 2030 in some models. By 2090, and under RCP8.5, such years are projected to become common (CSIRO and BOM, 2015). The number of annual snow days in New Zealand is projected to decrease under all RCPs, by up to 30 days or more by 2090 under RCP8.5, relative to 1986–2005 ( [[#MfE--2018|MfE, 2018]] ).

'''Glacier:''' Glacier mass and areal extent in New Zealand is projected to continue to decease over the 21st century ( ''high confidence'' ) ( [[IPCC:Wg1:Chapter:Chapter-9#9.5.1.3|Section 9.5.1.3]] ). Glacier ice volume from 1977–2018 in New Zealand has decreased from 26.6 to 17.9 km <sup>3</sup> (a loss of 33%; [[#Salinger--2019|Salinger et al., 2019]] ). Relative to 2015, glaciers in New Zealand are projected to lose 36 ± 44%, 53 ± 33% and 77 ± 27% of their mass by the end of the century under RCP2.6, RCP4.5 and RCP8.5 respectively, with the loss rates decreasing over time under RCP2.6 and increasing under RCP8.5 ( [[#Marzeion--2020|Marzeion et al., 2020]] ).

'''In summary, snowfall is expected to decrease throughout the region at high altitudes in both Australia''' ( high confidence ''') and New Zealand''' ( medium confidence '''). In New Zealand, glacier ice mass and extent are expected to decrease over the 21st century for all scenarios''' ( high confidence ''').'''

<div id="12.4.3.5" class="h3-container"></div>

<span id="coastal-and-oceanic-2"></span>