The influence of inter-annual temperature variability on the Greenland ice sheet
Uncertainties in the projected contribution of the Greenland ice sheet to future sea level rise mainly depend on uncertainties in the initial state of the present-day ice sheet. A previous study showed that including the inter-annual climate variability in the forcing of a simplified ice sheet model...
| Main Authors: | , , , , , |
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| Format: | Conference Object |
| Language: | English |
| Published: |
2023
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| Subjects: | |
| Online Access: | https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021604 |
| Summary: | Uncertainties in the projected contribution of the Greenland ice sheet to future sea level rise mainly depend on uncertainties in the initial state of the present-day ice sheet. A previous study showed that including the inter-annual climate variability in the forcing of a simplified ice sheet model leads to an increased mass loss rate, but the effect on the Greenland ice sheet is poorly known. Here we quantify the influence of inter-annual variability on mass loss from the Greenland ice sheet using the PISM model. We construct an ensemble of climate-forcing fields that accounts for inter-annual variability in temperature using reanalysis data products from RACMO and NOAA-CIRES. We investigate the Greenland ice sheet geometry's steady state and future evolution. We find that the steady-state ice sheet volume decreases by 0.24-0.38% when forced with a varying temperature forcing compared to a constant temperature forcing, equivalent to 21.7±5.0 mm of sea level rise (SLE). The northern basins are particularly sensitive with a change in volume of 1.2-0.9%. The response to abrupt warming is 0.03-0.21 mm SLE higher per year depending on climate scenario. Our results emphasize the importance of including temperature variability in projections of future mass loss. |
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