Greenland, Antarctica and Glaciers and Ice Caps mass balance from GRACE/GRACE-FO and other data

Abstract

<p>We discuss the state of mass balance of glaciers and ice sheets from 2002 to present using data from GRACE/GRACE-FO missions, after filling the gap between missions. We compare data processed by different centers (JPL, CSR, GFZ) and evaluate various Glacial Isotatic Adjustment models.  In Greenland, the data indicate a persistent mass loss at 251 Gt/yr, with an acceleration of 3 Gt/yr/yr, and large summer losses (400-600 Gt) in 2012, 2017, 2019. The mass balance regime has been evolving significantly in recent years, especially in the North, which holds the largest potential for rapid sea level rise. In Antarctica, ongoing mass losses in the Amundsen Sea Embayment of West Antarctica (122 Gt/yr), Antarctic Peninsula (26 Gt/yr), and Wilkes Land in East Antarctica (33 Gt/yr) dominate a small but significant increase in snowfall in the Queen Maud Land sector of East Antarctica since 2009 (47 Gt/yr). For the GIC, the mass loss averages 274 Gt/yr, with an acceleration of 4 Gt/yr/yr. The largest contributors are in the Arctic: Canadian Archipelago (70 Gt/yr), Alaska (72 Gt/yr), Russian Arctic (21 Gt/yr), Svalbard and Iceland (29 Gt/yr)) versus the southern hemisphere which is dominated by Patagonia (35 Gt/yr). High Mountain Asia averages 22 Gt/yr mass loss, with a large inter-annual variability. In regions not dominated by ice dynamics, the GRACE results compare better every year with output products from regional climate models (MAR, RACMO) forced by ERA5 and with global models such as NASA’s MERRA-2, which offers interesting perspectives for model development.</p> <p> </p>

Estimating the Mass Balance of the Antarctic Ice Sheet from 1985 to 2021 using the Input-Output Method

“…In the past few decades, the monitoring of ice sheet MB has primarily relied on three main methods: the gravity method, the altimetry method, and input-output method. Among these, the gravity method, facilitated by satellite missions such as GRACE (Gravity Recovery and Climate Experiment) and its successor GRACE-FO (GRACE Follow-On), has emerged as a significant means of directly and effectively monitoring ice sheet mass changes [4][5][6][7][8]. However, due to its relatively low spatial resolution (approximately 300 km) and susceptibility to glacier dynamic adjustments, GRACE/GRACE-FO cannot provide accurate and high-precision estimations of ice sheet mass changes.…”