Online Resource 3 Trends in wintertime deposition of ammonium, calcium, nitrate, and sulfate at individual Snowpack and NADP Wetfall sites in the Rocky Mountain region, 1993-2012

Snow pack depos ition Ammonium Calcium Nitrate Sulfate Site USGS kg/ha/y kg/ha/y kg/ha/y kg/ha/y name ID n r p Median r p Median r p Median r p Median Apgar Lookou 483105 t, 114011 Mont. 200 15 0.014 0.075 0.6 -- -- 0.2 0.013 0.428 2.2 -0.020 0.488 1.2 Banner 441812 Summi 115140 t, Idaho 400 11 -0.002 0.876 0.3 0.033 0.571 0.5 -0.072 0.005 1.0 0.036 0.640 0.8 Bertho ud 394800 Pass, 105470 Colo. 001 20 -0.001 0.897 0.4 0.047 0.003 0.8 -0.015 0.721 3.2 -0.015 0.381 1.4 Big Mounta 483029 in, 114204 Mont. 200 20 -0.004 0.381 0.4 -- -- 0.2 -0.057 0.006 2.3 -0.044 <0.001 1.3 Big 451638 Sky, 111255 Mont. 900 20 0.005 0.745 0.3 0.011 0.472 0.5 -0.029 0.315 1.5 -0.017 0.112 0.9 Brookl yn 412229 Lake, 106144 Wyo. 100 20 0.011 0.183 0.5 0.068 0.001 1.1 -0.039 0.284 3.5 -0.033 0.127 2.4 Brumle 390500 y, 106323 Colo. 000 20 0.003 0.160 0.2 0.037 0.007 0.6 0.016 0.417 1.6 -0.003 0.673 0.7 Buffalo 403240 Pass, 106410 Colo. 000 20 -0.001 0.820 1.0 0.037 0.133 1.5 -0.073 0.230 7.4 -0.221 <0.001 4.6 Camer on 403100 Pass, 105540 Colo. 000 20 -0.002 0.745 0.4 0.019 0.163 0.7 -0.091 0.003 3.1 -0.062 0.001 1.7 444303 Canyon 110304 , Wyo. 801 20 0.006 0.074 0.3 -- -- 0.1 -0.007 0.315 1.1 -0.012 0.025 0.5 Chief 454147 20 -0.001 0.820 0.3 -- -- 0.1 -0.014 0.163 0.9 -0.007 0.069 0.6 Joseph 113560 Pass, 900 Mont. Daisy 450303 Pass, 109571 Mont. 100 20 0.023 0.001 0.6 0.030 0.014 0.2 0.020 0.417 2.0 0.001 0.974 1.1 Divide 411817 Peak, 107093 Wyo. 500 19a 0.018 0.049 0.5 0.088 0.010 1.1 0.020 0.780 4.5 0.011 0.726 2.2 Dry 403200 Lake, 106470 Colo. 000 20 -0.001 0.720 0.4 0.022 0.048 0.7 -0.026 0.626 4.3 -0.071 <0.001 2.1 Dunckl ey 401200 Pass, 107090 Colo. 000 20 0.004 0.380 0.4 0.069 0.064 1.5 0.003 0.922 3.2 -0.013 0.417 1.7 Elk 405100 River, 106580 Colo. 000 20 0.006 0.172 0.3 0.055 <0.001 0.9 -0.056 0.041 3.2 -0.037 0.001 1.4 Elkhart 430010 Park, 109452 Wyo. 500 20 -0.002 0.558 0.3 0.009 0.143 0.3 -0.019 0.127 1.3 -0.025 0.009 0.8 Four Mile Meado 434900 w, 110160 Wyo. 000 20 0.006 0.085 0.2 0.008 0.120 0.2 0.003 0.871 0.9 -0.011 0.074 0.4 Fremon 392200 t Pass, 106120 Colo. 000 20 -- -- 0.2 0.016 0.183 0.7 -0.028 0.086 1.8 -0.020 0.091 0.8 Galena 435228 Summi 114425 t, Idaho 200 11 -0.006 0.533 0.2 0.048 0.330 0.4 -0.028 0.161 0.9 0.011 0.755 0.7 Garnet 434236 Canyon 110451 , Wyo. 300 20 0.010 0.228 0.6 0.041 0.041 0.6 0.021 0.496 2.3 -0.016 0.456 1.5 Grand 390158 Mesa, 107583 Colo. 901 20 -0.008 0.298 0.5 0.070 0.064 1.4 -0.059 0.012 3.0 -0.074 0.005 1.8 Granite 463828 Pass, 114364 Mont. 600 20 -- -- 0.2 -- -- 0.2 0.004 0.871 0.9 -0.006 0.538 0.7 Gypsu m 431345 Creek, 109594 Wyo. 600 19 -- -- 0.2 0.008 0.177 0.3 -0.011 0.093 1.2 -0.019 0.025 0.6 Hopew 364233 ell, N. 106145 Mex. 100 20 -0.003 0.435 0.3 0.024 0.136 1.0 -0.040 0.056 2.5 -0.042 0.010 1.4 Kings 465100 Hill, 110420 Mont. 000 20 -0.006 0.329 0.4 -0.005 0.527 0.4 -0.035 0.035 1.6 -0.043 0.001 0.8 Lake 402440 Irene, 105484 Colo. 700 20b 0.008 0.220 0.4 0.050 0.003 0.8 0.026 0.456 3.2 -0.009 0.496 1.6 Lewis Lake 441158 Divide, 110393 Wyo. 800 20 0.005 0.537 0.9 0.015 0.221 0.4 -0.060 0.006 2.6 -0.042 0.018 1.4 Lionsh 444142 ead, 111174 Mont. 700 20 -0.005 0.242 0.9 0.013 0.293 0.4 -0.050 0.030 2.8 -0.052 0.002 1.4 Loch Vale 401722 Forest, 105400 Colo. 300 18 -0.002 0.909 1.0 0.034 0.325 1.8 -0.171 <0.001 6.3 -0.133 0.003 3.1 Lovela nd 394000 Pass, 105533 Colo. 000 20 0.001 0.871 0.4 0.038 0.284 1.1 -0.089 0.086 2.8 -0.061 0.009 1.4 Molas 374500 Lake, 107420 Colo. 000 20 0.002 0.581 0.3 0.018 0.581 1.2 -0.017 0.673 2.5 -0.040 0.007 1.2 Monarc 383100 h Pass, 106193 Colo. 000 20 -- -- 0.3 0.041 0.086 1.3 -0.060 0.021 2.0 -0.028 0.041 1.1 Mount Belmo 464500 nt, 112195 Mont. 200 16 0.000 0.822 0.2 0.002 0.653 0.3 -0.021 0.300 1.0 -0.011 0.260 0.5 Noisy 480919 Basin, 113563 Mont. 600 20 -0.001 0.820 0.6 -- -- 0.2 -0.044 0.144 2.6 -0.025 0.315 1.4 Old 410917 Battle, 106583 Wyo. 300 20 0.015 0.135 0.7 0.079 0.001 1.2 -0.025 0.721 5.1 -0.053 0.035 3.0 Old Faithfu l fire 442722 Road, 110500 Wyo. 400 19 0.003 0.399 0.3 -- -- 0.2 -0.025 0.108 1.3 -0.022 0.050 0.6 Rabbit Ears 402355 Pass, 106392 Colo. 400 20 0.009 0.313 0.8 0.061 0.006 1.0 -0.051 0.284 5.2 -0.090 0.005 3.4 Red Mounta 375350 in Pass, 107420 Colo. 000 20 0.004 0.721 0.4 0.068 0.230 1.9 -0.028 0.417 3.0 -0.030 0.127 1.5 Red 454620 20 0.003 0.697 0.3 0.013 0.055 0.4 -0.009 0.626 1.3 -0.014 0.256 0.7 Mounta 112293 in, 100 Mont. Rendez vous Mounta 433603 in, 110522 Wyo. 100 20 0.025 0.009 0.6 0.043 0.033 0.6 0.022 0.456 1.9 0.005 0.820 1.5 Ripple Creek 400510 NADP, 107184 Colo.* 301 10 -0.009 0.858 0.5 0.016 0.854 1.5 -0.285 0.074 3.0 -0.103 0.107 1.4 Slumgu llion 375930 Pass, 107120 Colo. 000 20 0.001 0.648 0.1 0.028 0.183 0.9 -0.013 0.417 1.2 -0.017 0.015 0.6 Snow 470202 Bowl, 113592 Mont. 200 20 0.003 0.536 0.3 -- -- 0.2 -0.005 0.820 1.3 -0.009 0.538 1.0 South 423420 Pass, 108503 Wyo. 400 20 -0.005 0.269 0.3 0.023 0.015 0.6 -0.044 0.041 1.7 -0.036 0.005 1.2 Spring 463900 Gulch, 111280 Mont. 000 16 -0.011 0.031 0.2 0.002 0.751 0.2 -0.030 0.079 0.8 -0.020 0.017 0.3 Sunligh 392535 t Peak, 107224 Colo. 600 20 0.006 0.270 0.4 0.055 0.112 1.2 0.004 0.974 3.1 -0.027 0.230 1.6 Sylvan 442828 Lake, 110091 Wyo. 700 20 -0.001 0.794 0.4 -- -- 0.1 -0.021 0.183 1.6 -0.026 0.001 0.8 Taos Ski Valley, 363422 N. 105264 Mex. 300 13 -0.030 0.246 0.5 0.088 0.017 1.7 -0.154 0.127 3.0 0.045 0.428 2.5 Teton 433006 Pass, 110575 Wyo. 700 20 0.024 0.037 0.6 0.035 0.074 0.9 0.010 0.673 2.2 0.003 0.922 1.5 Togwot ee 434452 Pass, 110031 Wyo. 300 20 0.007 0.381 0.3 0.021 0.180 0.4 0.002 0.974 1.5 -0.025 0.230 0.8 Twenty -one 445548 Mile, 111032 Mont. 200 20 0.002 0.580 0.4 -- -- 0.1 -0.040 0.035 1.5 -0.030 0.002 0.6 Univer sity 400200 Camp, 105340 Colo. 000 20 0.000 0.922 0.6 0.035 0.021 0.8 -0.042 0.388 3.2 -0.051 0.012 2.1 West Yellow 443930 stone, 111052 Mont. 600 20 0.003 0.495 0.4 0.012 0.210 0.2 -0.018 0.390 1.2 -0.013 0.056 0.5 Wolf Creek 372900 Pass, 106470 Colo. 000 20 0.007 0.496 0.6 0.049 0.315 1.6 0.004 0.392 4.7 -0.098 0.010 2.9

NAD P Wetf all depos ition Ammonium Calcium Nitrate Sulfate Site Site kg/ha/y kg/ha/y kg/ha/y kg/ha/y name code n r p Median r p Median r p Median r p Median Beaver Meado ws NADP, Colo. CO19 20 0.006 0.183 0.2 0.009 0.025 0.2 0.002 0.974 1.2 -0.003 0.721 0.5 Brookl yn Lake NADP, Wyo. WY95 20 0.015 0.006 0.5 0.047 0.002 0.7 -0.014 0.770 3.7 -0.023 0.496 2.5 Buffalo Pass NADP, Colo. CO97 20 -0.001 0.974 0.6 0.021 0.056 0.6 -0.076 0.112 4.2 -0.145 0.001 3.2 Dry Lake NADP, Colo. CO93 20 -0.001 0.496 0.3 0.009 0.056 0.4 -0.065 0.007 3.4 -0.085 0.002 1.9 Four Mile Park NADP, Colo. CO08 20 -- -- 0.2 0.016 0.074 0.6 -0.014 0.230 1.4 -0.021 0.030 0.7 Glacier Park NADP, Mont. MT05 20 0.008 0.056 0.3 0.005 0.009 0.2 0.001 0.974 1.7 -0.018 0.064 0.9 Gypsu WY98 20 0.004 0.056 0.1 0.005 0.074 0.1 0.002 0.721 0.6 -0.002 0.581 0.3 m Creek NADP, Wyo. Loch Vale NADP, Colo. CO98 16 0.003 0.893 0.5 0.032 0.065 0.5 -0.061 0.163 3.0 -0.039 0.137 1.6 Lost Trail NADP, Mont. MT97 15 0.003 0.198 0.2 0.006 0.038 0.2 -0.004 0.767 1.0 0.004 0.553 0.6 Molas Pass NADP, Colo. CO96 19 0.004 0.184 0.2 0.013 0.162 0.6 -0.006 0.624 2.2 -0.022 0.208 1.2 Niwot NADP, Colo. CO02 19 0.011 0.401 1.2 -- -- 2.0 -0.200 0.069 10.9 -0.209 <0.001 5.2 Pinedal e NADP, Wyo. WY06 18 0.002 0.112 0.1 0.006 0.004 0.1 -0.001 0.940 0.6 -- -- 0.3 Snowy Range NADP, Wyo. WY00 19 0.012 0.363 0.8 0.060 0.014 1.0 -0.064 0.108 4.8 -0.063 0.162 3.2 South Pass NADP, Wyo. WY97 17 0.005 0.344 0.2 0.011 0.444 0.4 -0.033 0.260 1.5 -0.020 0.300 1.1 Sugarlo af NADP, Colo. CO94 20 -0.008 0.163 0.4 0.003 0.284 0.2 -0.045 0.064 1.6 -0.030 0.010 0.7 Sunligh t Peak NADP, Colo. CO92 18 0.004 0.289 0.2 0.025 0.023 0.6 0.005 0.880 1.9 -0.021 0.041 1.1 Wolf Creek Pass NADP, Colo. CO91 19 0.016 0.108 0.7 0.036 0.184 1.3 -0.024 0.529 5.0 -0.135 0.036 3.6

Slope values determined by Seasonal Kendall tests for trends are expressed as kilograms per hectare per year (kg/ha/yr) for ammonium, calcium, nitrate, and sulfate; median values are in kg/ha. Significant slopes with p-values (p) less than or equal to 0.15 are shown in bold. Upward trends are positive; downward trends are negative. "--" indicates p-value near 1 and no trend was computed Snowpack deposition was calculated as concentration times SWE equals deposition, using data from links listed below Tables 3 and 5. Time-series data for NADP Wetfall deposition may be viewed at: http://nadp.sws.uiuc.edu/data/ntn/

*Ripple Cr. NADP is the name of a Snowpack site co-located with an NADP site. This Snowpack site was used in this study, but the co-located NADP Dry Deposition site was not aAt this site, n = 18 for ammonium; for other constituents n = 19 bAt this site, n = 19 for ammonium; for other constituents n = 20