![]() So, numbers are just kind of all over the board this year. Whereas the central Puget, in that Everett/Seattle convergence zone is 106% of typical. The North Puget Sound, again the furthest away from the storm tracks, is sitting at 88% of average. And we see the same thing with the West side. And Klickitat is at 89%, Naches is 87% which is a little bit of an increase from a few days ago. “As a good example, right now on the lower Yakima we're still sitting at only 83% of normal we just can't seem to catch a break there in that area. And he added the inconsistency is occurring on both sides of the Cascades. Pattee noted that snowpack numbers right now run from just under 110% of average to the low 80s. The density of North Cascade glacier snowpack has been found to be essentially to within the range of accuracy of the measurement instruments (0.580.60 g/cm 3) constant by August and density measurements are only completed during June measurements (Pelto, 1996 Krimmel, 1999). And so we haven't really gained a lot you know that that 99% is only two percentage points more than we were just six days ago before this last storm cycle hit.” mu.equiv/L.) The composition of the waters in terms of alkalinity and calcium concentration was similar to that of nonacidified waters of northwestern Norway and northwestern Ontario.“As much as anything, except in just a couple of isolated places, in the state, it’s kind of been maintenance snow that we've been getting and precipitation. All of the source lakes were found to be susceptible but not acid, with alkalinities ranging from 4 to 190. Twenty-nine watershed source lakes lying along the Cascade Crest 3-20 miles north of the precipitation collectors were sampled during the summer of 1981. The strong more » acid content of the samples was observed to increase in the summer months. The sulfate deposition for 1981 at the Cascade Crest is estimated to be 16.0 kg ha/sup -1/ year/sup -1/ of SO/sub 4/ (sea salt corrected). The average strong acid composition in terms of sulfate and nitrate over the five collector sites ranged from 57 to 62 equiv % sulfuric acid. The volume weighted average pH over the collection period at the Cascade Crest (Snoqualmie Pass) was 4.71. « lessīulk precipitation was monitored at five sampling sites across the Cascade mountains east and windward of the urban Puget Sound area January 1981 through July 1981. This suggests that the pattern of snowpack melt and especially the pathway the meltwater follows to the stream may be important factors in determining whether stream water chemical pulses occur. An estimated 30% of the SO/sub 4//sup -2/ in the lake was derived from the = concentration, the magnitude and rate of concentration change was as great in a year of small peak snowpack ion load as it was following a more rapid ion loss from a larger snowpack load. By comparing lake water NO/sub 3//sup -/ concentrations to snowpack concentrations, over 75% of the NO/sub 3//sup -/ in the lake could be attributed to a snowpack source. During snow melt runoff there was no apparent neutralization of bicarbonate by strong acids. Acid neutralizing capacity at the lake outlet during snow melt was diluted to 50% of April premelt values. mu.eq L/sup -1/, respectively, and mean pH was 5.48. By July, mean NO/sub 3//sup -/ and SO/sub 4//sup -2/ concentrations were 0.32 and 1.73. During melting, anion levels in the snowpack decreased and pH increased. Mean concentrations of NO/sub 3//sup -/ and SO/sub 4//sup -2/ from North Cascades snowpack were near 4.5 and 5.5. Integrated snowpack samples and lake water samples were collected from a low-alkalinity watershed in the North Cascades in 19 and analyzed for inorganic chemical parameters.
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