Cryolisters, I’ll start by thanking Todd Albert for maintaining
Cryolist. It made this soooo easy. Todd asked me to compile the responses that I received and
share it with the list. After just a few hours, here were the most informative
replies (minus the many that quickly steered me toward the Bahr & Dygerov
reference with the figure of 160,000 glaciers in it). Thanks to everyone! 1--from Hester Jiskoot For a number of years now I have
been using the rough number of 160,000 based on Bahr and Dyurgerov
(1999). In my PhD thesis from 1999 (see
Table 1.1 on p. 7 and 8: http://people.uleth.ca/~hester.jiskoot/pages/publications/Jiskoot_H_PhD_1999.pdf)
I verified their number based on counting and extrapolation of a published
glacier numbers estimated around the world. The total number of glaciers I
calculated from the sum of all regions was 157122, very close to the Bahr and
Dyurgerov estimate. This number includes an estimate of Antarctic
peninsula local ice that is half the number of the local glaciers around the
Greenland Ice Sheet. The above total glacier number
include all glacier types (incl. rock glaciers, neves, etc). I also roughly
estimated on the basis of the distribution of 'true' glaciers (mountain
glaciers and up) by excluding glaciers smaller than 1km2 in a number of regions
(e.g. Svalbard and the Yukon Territory) that the total number of glacier
>1km2 is about 50% of 160 000. On the basis of the above calculations in my
PhD thesis I did publish a number of "more than 100,000 glaciers
world-wide" in Jiskoot et al. (1998). Bahr, D.B., and Dyurgerov, M.B.,
1999. Characteristic mass-balance scaling with valley glacier size. J.
Glaciol. 45 (149), 17-21. Jiskoot, H, P Boyle & T
Murray, 1998. The incidence of glacier surging in Svalbard: results from
multivariate statistics. Computers
and Geosciences 24
(4), 387-399. 2—from Jeff Key ( I like it because it reminds us all of the
IGOS Cryosphere volume) In
our IGOS Cryosphere Theme report there is a statement that "The total
number of glaciers has been estimated by statistical scaling to about 160,000
(Meier and Bahr, 1996), covering an area of about 785m999 km2 (Dyurgerov and
Meier, 2005)". The Meier and Bahr reference is a CRREL Special Report,
96-27, 98-94, "Counting Glaciers: Use of scaling methods to estimate the
number and size distribution of the glaciers of the world". The other
reference is Dyurgerov, M.B. and M.F. Meier, 2005, Glaciers and the changing
earth system: a 2004 snapshot", INSTAAR Occasional Paper, OP-58. 3—from Tad Pfeffer The answer obviously depends on what
lower size limit you choose, but the largest number that gets quoted is 200,000
- 400,000 glaciers, with a cutoff at 1 km^2. Bahr and Meier (2009) use this,
quoting Dyurgerov and Meier's INSTAAR Occasional Paper #58 (2006).... but, I
can't actually find the number in Dyurgerov and Meier. You might contact Dave
Bahr <[hidden email]> about
this (I actually had exactly this conversation with him the other day). Other
analyses suggest that there are an enormous number of uncounted glaciers, and
it's pretty easy to get up to ca. 200,000 with conservative estimates. 4—from Jason Box (not actually the answer to the
question I asked, but interesting numbers, so I added it) Based on MODIS data, I calculated
0.389 million sq km isolated ice masses in Greenland of at least 0.0625 sq km
in area totaling 69,489 sq km outside the inland ice sheet, total glaciated
area: 1.818 million sq km. The work is unpublished :-/ but use the numbers if
you want. I certainly got what I need—and more! Bob +++++++++++++++++++++++++++++++++++++++++ Dr. Robert Bindschadler Emeritus Scientist Hydrospheric and Biospheric
Sciences Laboratory Code
614 Bldg. 33, Rm. A112 NASA Goddard Space Flight
Center 301-614-5707 Greenbelt, MD
20771 301-614-5666 (Fax) USA
[hidden email] "None of us is as smart
as all of us." Japanese proverb _______________________________________________ You're subscribed to the CRYOLIST mailing list To change your subscription options, visit http://cryolist.org/ To send a message to the list, email [hidden email] |
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