Open Access Repository

Antarctic surface mass balance: natural variability, noise and detecting new trends

Downloads

Downloads per month over past year

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.

[img]
Preview
PDF
139380.pdf | Download (848kB)

| Preview

Abstract

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.

Item Type: Article
Authors/Creators:King, MA and Watson, CS
Keywords: Antarctic surface mass balance, noise, trends
Journal or Publication Title: Geophysical Research Letters
Publisher: Wiley-Blackwell Publishing Ltd
ISSN: 1944-8007
DOI / ID Number: 10.1029/2020GL087493
Copyright Information:

Copyright 2020 American Geophysical Union

Related URLs:
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page
TOP