Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A....
-
Upload
rudolf-francis -
Category
Documents
-
view
215 -
download
0
Transcript of Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A....
![Page 1: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/1.jpg)
Simulating the Response of Two Wyoming Glaciers to Projected 21rst Century Warming
Mitchell A. Plummer,Idaho National Laboratory
L. DeWayne CecilU.S.Geological Survey
![Page 3: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/3.jpg)
Te
ton
Ran
ge
Wind River Range
![Page 4: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/4.jpg)
Net annual ice balance, bn
• bn = net ice budget at any location in the x,y plane
• Snow = total snowfall
– Fraction of precipitation falling as snow
• M = mass of snow melted
– Calculated from energy balance when T > 0
• E = evaporation & sublimation
– Calculated via turbulent heat transfer equations
dtEMSnowdtESnowbfall
spring
spring
falln )()(
![Page 5: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/5.jpg)
![Page 6: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/6.jpg)
T = -6ºC
![Page 7: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/7.jpg)
![Page 8: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/8.jpg)
Modeled Glaciers and Perennial Snow Mapped Glaciers and Perennial Snow
![Page 9: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/9.jpg)
Gra
nd
Tet
on
Cas
cad
e C
anyo
n
Jenny Lake
Mo
un
t Sain
t Joh
n
Photo by Ed
Williams, BYU
Idaho
![Page 10: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/10.jpg)
![Page 11: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/11.jpg)
Base case
+1.0 °C+0.5 °C
![Page 12: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/12.jpg)
![Page 13: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/13.jpg)
![Page 14: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/14.jpg)
![Page 15: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/15.jpg)
Base case
![Page 16: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/16.jpg)
+0.5ºC
![Page 17: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/17.jpg)
+1.0ºC
![Page 18: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/18.jpg)
+1.5ºC
![Page 19: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/19.jpg)
+2.0ºC
![Page 20: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/20.jpg)
+2.5ºC
![Page 21: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/21.jpg)
![Page 22: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/22.jpg)
Upper Fremont Glacier
LowerFremont Glacier
Knifepoint Glacier
Titcomb basin
![Page 23: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/23.jpg)
![Page 24: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/24.jpg)
August 1990
firn line,3980 m
Naftz et al. 2002
![Page 25: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/25.jpg)
![Page 26: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/26.jpg)
![Page 27: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/27.jpg)
![Page 28: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/28.jpg)
![Page 29: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/29.jpg)
-350
-300
-250
-200
-150
-100
-50
0
50
100
0 100 200 300 400 500 600 700
No
rm
alize
d m
ass b
ala
nce
Elapsed time (yrs)
0
2e+007
4e+007
6e+007
8e+007
1e+008
1.2e+008
1.4e+008
1.6e+008
0 100 200 300 400 500 600 700
To
tal ic
e v
olu
me
(m
^3
)
Elapsed time (yrs)
Max ice thickness (m
)
40
60
80
100
120
140
160
180
200
Tota
l ic
e v
olu
me (
m3)
1. Modern glacier too large
2. Modern glacier just right (+0.25ºC)
3. Five 0.25ºC temperature
increases applied
Glacier allowed to return to
steady state
{
![Page 30: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/30.jpg)
Conclusions• Modeling experiments suggest that a temperature increase of ~1.5°C
would effectively eliminate the Teton and Lower Fremont glaciers
– Apparent sensitivity of Fremont glacier appears inconsistent with the USGS 18O temperature record but lapse rate variations not yet explored
• At late 20th century global warming rates (~0.1°C / decade), it could take as long as 150 – 200 years to dramatically increase the biodiversity of these locations
• Global climate models scaled to the Pacific NW project an increase in average temperature on the order of 0.2°-0.6°C (0.3°-1°F) per decade throughout the 21st century, so maybe we can get to that species richness in 50 – 100 yrs.
• Response times matter. Two retreating glaciers of different size may well be responding to completely different phenomena.
• Uncertainties? Yes, but …
![Page 31: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/31.jpg)
Questions• Barring ‘local’ redistribution of snow by wind, avalanching
etc, how variable is precipitation across short distances in the mountains and how would one capture that in a simple model?
• In paleoglacier modeling,
– How is a large change in mountain precipitation distributed vertically?
– How reasonable is it to assume constant lapse rates?
• Are pseudo-vertical lapse rates related to vertical precipitation gradients?
• Need more data to describe mountain climate and its variability
![Page 32: Simulating the Response of Two Wyoming Glaciers to Projected 21 rst Century Warming Mitchell A. Plummer, Idaho National Laboratory L. DeWayne Cecil U.S.Geological.](https://reader035.fdocuments.net/reader035/viewer/2022081516/56649e745503460f94b74d44/html5/thumbnails/32.jpg)
Photo by Ed Williams, BYU Idaho
Terminus