Antarctic surface mass balance: natural variability, noise and detecting new trends
The emergence of new, statistically robust trends in Antarctic surface mass balance (SMB) requires an understanding of the underlying SMB variability (noise). We show that simple white or AR[1] noise models do not adequately represent the variability of SMB in both the RACMO2.3p2 SMB model output (1...
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Online Access: | https://eprints.utas.edu.au/33924/ https://eprints.utas.edu.au/33924/2/139380.pdf |
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ftunivtasmania:oai:eprints.utas.edu.au:33924 2023-05-15T13:31:54+02:00 Antarctic surface mass balance: natural variability, noise and detecting new trends King, MA Watson, CS 2020 application/pdf https://eprints.utas.edu.au/33924/ https://eprints.utas.edu.au/33924/2/139380.pdf en eng Wiley-Blackwell Publishing Ltd https://eprints.utas.edu.au/33924/2/139380.pdf King, MA orcid:0000-0001-5611-9498 and Watson, CS orcid:0000-0002-7464-4592 2020 , 'Antarctic surface mass balance: natural variability, noise and detecting new trends' , Geophysical Research Letters , doi:10.1029/2020GL087493 <http://dx.doi.org/10.1029/2020GL087493>. Antarctic surface mass balance noise trends Article PeerReviewed 2020 ftunivtasmania https://doi.org/10.1029/2020GL087493 2021-10-04T22:18:08Z The emergence of new, statistically robust trends in Antarctic surface mass balance (SMB) requires an understanding of the underlying SMB variability (noise). We show that simple white or AR[1] noise models do not adequately represent the variability of SMB in both the RACMO2.3p2 SMB model output (1979-2017) and composite ice core records (1800-2010), under-estimating low-frequency variability. By testing a range of noise models, we find that a Generalized Gauss Markov (GGM) model better approximates the noise around a linear trend. The general preference for GGM noise applies over spatial scales from the total ice sheet down to individual drainage basins. Over the longest timescales considered, trend uncertainties are 1.3-2.3 times larger using a GGM model compared to using an AR1 model at the ice sheet scale. Overall, our results suggest that larger trends or longer periods are required before new SMB trends can be robustly separated from background noise. Article in Journal/Newspaper Antarc* Antarctic ice core Ice Sheet University of Tasmania: UTas ePrints Antarctic Geophysical Research Letters 47 12 |
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Open Polar |
collection |
University of Tasmania: UTas ePrints |
op_collection_id |
ftunivtasmania |
language |
English |
topic |
Antarctic surface mass balance noise trends |
spellingShingle |
Antarctic surface mass balance noise trends King, MA Watson, CS Antarctic surface mass balance: natural variability, noise and detecting new trends |
topic_facet |
Antarctic surface mass balance noise trends |
description |
The emergence of new, statistically robust trends in Antarctic surface mass balance (SMB) requires an understanding of the underlying SMB variability (noise). We show that simple white or AR[1] noise models do not adequately represent the variability of SMB in both the RACMO2.3p2 SMB model output (1979-2017) and composite ice core records (1800-2010), under-estimating low-frequency variability. By testing a range of noise models, we find that a Generalized Gauss Markov (GGM) model better approximates the noise around a linear trend. The general preference for GGM noise applies over spatial scales from the total ice sheet down to individual drainage basins. Over the longest timescales considered, trend uncertainties are 1.3-2.3 times larger using a GGM model compared to using an AR1 model at the ice sheet scale. Overall, our results suggest that larger trends or longer periods are required before new SMB trends can be robustly separated from background noise. |
format |
Article in Journal/Newspaper |
author |
King, MA Watson, CS |
author_facet |
King, MA Watson, CS |
author_sort |
King, MA |
title |
Antarctic surface mass balance: natural variability, noise and detecting new trends |
title_short |
Antarctic surface mass balance: natural variability, noise and detecting new trends |
title_full |
Antarctic surface mass balance: natural variability, noise and detecting new trends |
title_fullStr |
Antarctic surface mass balance: natural variability, noise and detecting new trends |
title_full_unstemmed |
Antarctic surface mass balance: natural variability, noise and detecting new trends |
title_sort |
antarctic surface mass balance: natural variability, noise and detecting new trends |
publisher |
Wiley-Blackwell Publishing Ltd |
publishDate |
2020 |
url |
https://eprints.utas.edu.au/33924/ https://eprints.utas.edu.au/33924/2/139380.pdf |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic ice core Ice Sheet |
genre_facet |
Antarc* Antarctic ice core Ice Sheet |
op_relation |
https://eprints.utas.edu.au/33924/2/139380.pdf King, MA orcid:0000-0001-5611-9498 and Watson, CS orcid:0000-0002-7464-4592 2020 , 'Antarctic surface mass balance: natural variability, noise and detecting new trends' , Geophysical Research Letters , doi:10.1029/2020GL087493 <http://dx.doi.org/10.1029/2020GL087493>. |
op_doi |
https://doi.org/10.1029/2020GL087493 |
container_title |
Geophysical Research Letters |
container_volume |
47 |
container_issue |
12 |
_version_ |
1766022264790188032 |