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ESTIMATED CHANGE IN VOLUME, 1896-2021 (Beason et al., 2023):
PLEASE see important notes about this, below...
Glacier-specific Scaling Parameter, c:
0.030816
| Units |
1896 |
1913 |
1971 |
1994 |
2009 |
2015 |
2021 |
| Volume, mi3 |
0.1255 |
0.0647 |
0.0500 |
0.0505 |
0.0378 |
0.0340 |
0.0317 |
| Volume, km3 |
0.5233 |
0.2696 |
0.2082 |
0.2104 |
0.1575 |
0.1417 |
0.1323 |
Volume Change Between Periods
|
1913 |
1971 |
1994 |
2009 |
2015 |
2021 |
| 1896 | -0.061 mi3
(-0.254 km3) | -0.076 mi3
(-0.315 km3) | -0.075 mi3
(-0.313 km3) | -0.088 mi3
(-0.366 km3) | -0.092 mi3
(-0.382 km3) | -0.094 mi3
(-0.391 km3) |
|---|
| 1913 | -- | -0.015 mi3
(-0.061 km3) | -0.014 mi3
(-0.059 km3) | -0.027 mi3
(-0.112 km3) | -0.031 mi3
(-0.128 km3) | -0.033 mi3
(-0.137 km3) |
|---|
| 1971 | | -- | 0.001 mi3
(0.002 km3) | -0.012 mi3
(-0.051 km3) | -0.016 mi3
(-0.067 km3) | -0.018 mi3
(-0.076 km3) |
|---|
| 1994 | | | -- | -0.013 mi3
(-0.053 km3) | -0.016 mi3
(-0.069 km3) | -0.019 mi3
(-0.078 km3) |
|---|
| 2009 | | | | -- | -0.004 mi3
(-0.016 km3) | -0.006 mi3
(-0.025 km3) |
|---|
| 2015 | | | | | -- | -0.002 mi3
(-0.009 km3) |
|---|
Percent Change Between Periods
|
1913 |
1971 |
1994 |
2009 |
2015 |
2021 |
| 1896 | -48.48% | -60.21% | -59.80% | -69.90% | -72.92% | -74.72% |
|---|
| 1913 | -- | -22.76% | -21.97% | -41.59% | -47.44% | -50.94% |
|---|
| 1971 | | -- | 1.02% | -24.37% | -31.95% | -36.48% |
|---|
| 1994 | | | -- | -25.14% | -32.63% | -37.13% |
|---|
| 2009 | | | | -- | -10.01% | -16.02% |
|---|
| 2015 | | | | | -- | -6.67% |
|---|
Important comments about the calculation of volume shown here
The calculation of glacial volume shown on this page is based on an analysis of two methods used at Mount Rainier in the past (Driedger and Kennard [1986]; and Nylen [2001]) as well as the most recent literature review for glacier area-volume scaling (Please review Beason et al. [2023] for an in-depth discussion about this issue). It should be noted that simply converting area to volume with an equation is extremely difficult and the values presented here have extremely large error margins (likely ± 35% or more). With that in mind, the values presented here should give you an estimate of the glacial volume and change in volume over time. Please use these data very carefully with those caveats.
The calcuation of the volume is as follows:
\[V_i = {(c_iA_i^{1.375}) + (c_nA_i^{1.36}) \over 2}\]
Where:
\(V_i\) = Average volume for the glacier in question (km3);
\(c_i\) = The glacier-specific scaling parameter (back-calculated from glacier area and volume in 1971 in Driedger and Kennard (1986); Method described in Beason et al. (2023). The value for the Puyallup Glacier is 0.030816 (this is also listed above the volume graph);
\(c_n\) = The back-calculated scaling parameter from Nylen (2001) of 0.0255; and
\(A_i\) = The measured volume of the glacier in question (km2).
This is essentially an average of the back-calculated Dreidger and Kennard (1986) and Nylen (2001) methods (D&K is in the first parenthesis; Nylen in the second). For example, for the Puyallup Glacier in 2021, you can find the following individual volumes:
Back-calculated Dreidger and Kennard (1986) Method: 0.0350 mi3 (0.1459 km3).
Back-calculated Nylen (2001) Method: 0.0285 mi3 (0.1187 km3).
Average of the two (above equation and values listed for 2021 here): 0.0317 mi3 (0.1323 km3).
Official volume estimate listed above, with error: 0.0317 ± 0.0111 mi3 (0.1323 ± 0.0463 km3).
As you can see, the D&K method tends to produce higher values and Nylen produces lower values; the average of these two methods probably estimates the glacial volume. Until further research is done in this area and we can develop a better method or equation to determine volumes, this is the method we are using to determine glacial volumes. For more information about this method, please read the methods section of Beason et al. (2023).
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