Now that we have covered all the boring details of how these gadgets work, let's look at some results. For this article we will discuss only the results for the 2000 summer season; the results from previous years will have to wait for a future article.

There are monitors on 19 front-country geysers at this writing. Some have been in place since May, others were acquired during the summer and have only been in place a month or so. This article covers only the highlights; a more in-depth examination is more suited for a GOSA Transactions article.

Geyser Hill

I have had an interest in Geyser Hill for many years, and my research permit is primarily aimed at monitoring activity there. There are loggers on Aurum, Lion, Little Cub, Depression, Plume, Plate, and Boardwalk Geysers.

Aurum

As we have come to expect, dry weather resulted in long and erratic intervals for this geyser. The logger was first deployed in late June after the wet weather ended. There were only a handful of intervals in the usual "short interval" range of 2:30 to 2:45, (six under 2:35, and only 24 between 2:35 and 3:00. During the previous few years, these short intervals have been much more common, and recurred for a few days following heavy rain. This year, even after rainfall, the sub-2:45 intervals did not occur. There were ten intervals over eight hours, one reaching 11:58 on 4 August. For the three months for which data is available there was a slight trend to increased intervals, with a few periods of a 2-3 days of shorter intervals following wet weather.

We had an autumn snow starting on 21 September, with about a foot of accumulation at Old Faithful (and with most of the roads closed for a day). Starting at midnight on the 22nd, about the time the snow started to accumulate, Aurum's intervals dropped to between 2 hours 31 minutes and four hours. The short intervals only continued until the snow melted; long intervals resumed at noon on 24 September.

Lion

The logger on Lion has a most unfriendly environment, as the logger is immersed in very hot water on every eruption. I had one logger destroyed here, but the current logger, in a waterproof case, has survived for both 1999 and 2000 so far. This summer's activity was fairly uniform, with only a few really long intervals between series-two intervals in late July were well over 12 hours, but the great majority of initial eruption to initial eruption intervals were between six and ten hours, with the median series interval being 7:29. The intervals between series gradually decreased from about 8:30 early in the summer to the present average of around seven hours.

The big change this summer from the behavior in the past few years was the total absence of long series. The longest series recorded was five eruptions, and there were only three of these, all of which included a minor eruption. Fully 58% of the series consisted of two eruptions. As has been the case for the three years that I have monitored Lion, there is only a weak relationship between the number of eruptions in a series and the following interval.

Little Cub -- [ Charts ]

Little Cub is a good example of where a data logger can reveal information about a geyser that is often seen but not often recorded. The logbook has large numbers of "in eruption" and "near start" notations, so there are few intervals available from that source, and almost none during the night hours. With the data logger it is possible to record intervals and durations with pretty good accuracy (the end of the eruption is difficult to determine exactly from the temperature record).

This year, Little Cub's intervals have been fairly steady at about I hour 22 minutes all summer, until late September. Early in the season, until about the first of August, there were occasional short intervals, some under one hour, which tended to occur in the afternoon between 12:00 and 18:00.

This trend to a diurnal pattern early in the season has been apparent in 1998 and 1999, to a greater extent than in 2000. After early August, there was a cyclic variation of intervals with a period for the whole cycle of about one week, plus or minus a day or two. The periods of longer intervals appeared to coincide (within a day or so) with SMax as indicated by eruptions of Little Squirt.

On 8 September there was a cycle with noticeably longer intervals, and especially with an absence of short intervals. The intervals returned to normal 1:25 or so until 19 September when there was an interval of 1:51 recorded, followed by two days (again, the snow days...) when the intervals rose to about 1:40.