Tony Heller on Greenland's Mass Balance

Greenland's Contribution to Sea Level Rise Since 1992

In 2019, Tony Heller posted on his blog that "Over the past three years, Greenland’s surface has gained 1.2 trillion tons of new ice... Experts in the press corps have generously interpreted the data for us, and determined that there is a climate emergency and it is President Trump’s fault." He then showed graphs supporting that Greenland's surface mass balance (SMB) did indeed gain ice each of those years, totaling 1.2 trillion tons of ice. 

What Heller doesn't tell you is that Greenland's SMB gains ice pretty much every year, but it also loses ice every year due to glacial calving and basal melting; this is referred to as discharge (D). In order to assess whether Greenland gained or lost ice, what is referred to as total mass balance (TMB) you have to account for both SMB and D. The equation for this is not that hard:

TMB = SMB + D

Heller was capable of looking up the value for SMB but neglected to look up values for D. So I pointed this out to him in the comments. His response was rather entertaining.


Apparently, data Heller can use to say Greenland's surface gained ice is fine, but the data that shows that Greenland as a whole has lost ice every year since the 1990s is "difficult to measure and is largely unrelated to climate." It's not like Heller doesn't have access to the data that proves him wrong, and I linked to an IMBIE study that would give him the data he needed to produce an accurate accounting of the Greenland Ice Sheet.[8]


The study provides a comprehensive accounting of the GrIS ass balance from 1992 to 2018. They conclude, "Cumulative ice losses from Greenland as a whole have been close to the rates predicted by the Intergovernmental Panel on Climate Change for their high-end climate warming scenario17, which forecast an additional 70 to 130 millimetres of global sea-level rise by 2100 compared with their central estimate." This what the cumulative mass loss looks like.


Below I compiled a list of references that provide evidence that is more than sufficient to conclude that Greenland is in fact losing ice and contributing to sea level rise.


[1] Norris, J., Allen, R., Evan, A. et al. Evidence for climate change in the satellite cloud record. Nature 536, 72–75 (2016). https://doi.org/10.1038/nature18273
https://www.nature.com/articles/nature18273?foxtrotcallback=true

[2] Hofer 2017, "Decreasing cloud cover drives the recent mass loss on the Greenland Ice Sheet." Science Advances 28 Jun 2017: Vol. 3, no. 6, e1700584 DOI: 10.1126/sciadv.1700584
https://advances.sciencemag.org/content/advances/3/6/e1700584.full.pdf

[3] Box et al, “Global sea-level contribution from Arctic land ice: 1971–2017” Environmental Research Letters 13.12 (2018)
https://iopscience.iop.org/article/10.1088/1748-9326/aaf2ed

[4] Michael Bevis, Christopher Harig, Shfaqat A. Khan, Abel Brown, Frederik J. Simons, Michael Willis, Xavier Fettweis, Michiel R. van den Broeke, Finn Bo Madsen, Eric Kendrick, Dana J. Caccamise, Tonie van Dam, Per Knudsen, Thomas Nylen. Accelerating changes in ice mass within Greenland, and the ice sheet’s sensitivity to atmospheric forcing. Proceedings of the National Academy of Sciences Feb 2019, 116 (6) 1934-1939; DOI: 10.1073/pnas.1806562116
https://www.researchgate.net/publication/330549231_Accelerating_changes_in_ice_mass_within_Greenland_and_the_ice_sheet's_sensitivity_to_atmospheric_forcing

[5] JĂ©rĂ©mie Mouginot, Eric Rignot, Anders A. Bjørk, Michiel van den Broeke, Romain Millan, Mathieu Morlighem, Brice NoĂ«l, Bernd Scheuchl, Michael Wood, “Forty-six years of Greenland Ice Sheet mass balance from 1972 to 2018” PNAS May 7, 2019 116 (19) 9239-9244; first published April 22, 2019 https://doi.org/10.1073/pnas.1904242116
https://www.pnas.org/content/116/19/9239

[6] Mouginot et al, “Supplementary Information for Forty-six years of Greenland Ice Sheet mass balance from 1972 to 2018” https://www.pnas.org/content/pnas/suppl/2019/04/17/1904242116.DCSupplemental/pnas.1904242116.sapp.pdf

[7] “Dataset_S02 (XLSX).” Supporting Information for Mouginot et al 2019 with D, SMB and TMB data for 1972-2018. Clicking the link should download an Excel file. https://www.pnas.org/highwire/filestream/860129/field_highwire_adjunct_files/2/pnas.1904242116.sd02.xlsx

[8] The IMBIE Team., Shepherd, A., Ivins, E. et al. Mass balance of the Greenland Ice Sheet from 1992 to 2018. Nature 579, 233–239 (2020). https://doi.org/10.1038/s41586-019-1855-2
https://www.nature.com/articles/s41586-019-1855-2

[9] Simonsen, S. B., Barletta, V. R., Colgan, W. T., & Sørensen, L. S. (2021). Greenland Ice Sheet mass balance (1992–2020) from calibrated radar altimetry. Geophysical Research Letters, 48, e2020GL091216. https://doi.org/10.1029/2020GL091216

[10] Slater, T., Lawrence, I. R., Otosaka, I. N., Shepherd, A., Gourmelen, N., Jakob, L., Tepes, P., Gilbert, L., and Nienow, P.: Review article: Earth's ice imbalance, The Cryosphere, 15, 233–246, https://doi.org/10.5194/tc-15-233-2021, 2021.
https://tc.copernicus.org/articles/15/233/2021/?fbclid=IwAR0qOWWg3JLWHHiwtqlOMBKvaNBAKnYbbQBp4vybS_KO8XVNYGaGb96yXKw


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