• DOI:10.5194/egusphere-egu2020-7084
• Corpus ID: 221877214

The transient sensitivity of sea level rise

@article{Grinsted2020TheTS,
  title={The transient sensitivity of sea level rise},
  author={Aslak Grinsted and Jens Hesselbjerg Christensen},
  journal={Ocean Science},
  year={2020}
}

• A. Grinsted, J. Christensen
• Published 23 March 2020
• Environmental Science
• Ocean Science

Abstract. Recent assessments from the Intergovernmental Panel on
Climate Change (IPCC) imply that global mean sea level is unlikely to rise
more than about 1.1 m within this century but will increase further beyond
2100. Even within the most intensive future anthropogenic greenhouse gas
emission scenarios, higher levels are assessed to be unlikely. However, some
studies conclude that considerably greater sea level rise could be realized,
and a number of experts assign a substantially higher likelihood of such a
future. To understand this discrepancy, it would be useful to have scenario-independent metrics that can be compared between different approaches. The
concept of a transient climate sensitivity has proven to be useful to
compare the global mean temperature response of climate models to specific
radiative forcing scenarios. Here, we introduce a similar metric for sea
level response. By analyzing the mean rate of change in sea level (not sea level
itself), we identify a nearly linear relationship with global mean surface
temperature (and therefore accumulated carbon dioxide emissions) both in model projections and in observations on a century scale. This
motivates us to define the “transient sea level sensitivity” as the increase
in the sea level rate associated with a given warming in units of
meters per century per kelvin. We find that future projections estimated on climate model
responses fall below extrapolation based on recent observational records.
This comparison suggests that the likely upper level of sea level
projections in recent IPCC reports would be too low.