GOSA (The Geyser Observation and Study Association)

Summary of Electronically Recorded Geyser Activity
Compiled By
Ralph Taylor


Activity for many of Yellowstone's geysers is tracked via electronic data loggers.  The data loggers keep a record of temperature in the runoff channels from which the eruption times can be determined.  For a more detailed discussion, follow the Background Information link below.

At the end of the 2003 summer season there were nearly 40 data loggers deployed on geysers and hot springs in Yellowstone.  During the summer months, from late June until late September, the loggers are downloaded weekly and the analysis results are updated as frequently as time permits.  During the rest of the year, some of the loggers are removed and others are deployed with longer sample times to allow a reasonably long record.

The record for 2003 is complete through the end of the year for most geysers, but a few are incomplete because the final data has not yet been retrieved.  Most of the geysers with data loggers deployed over the winter have been analyzed at this time, and the 2004 statistics are posted. 

The data pages are arranged with the statistics for the seven days preceding the download in the first table, the statistics for the month preceding the download in the second table, and statistics for all of the data recorded in the year in the last table.  The start and end dates covered for each geyser are shown since the coverage varies from geyser to geyser.  In some cases the record is not continuous.  Gaps occur when the data logger memory fills before the data can be downloaded (this often occurs late in the spring), and sometimes when technical problems interrupt the recording. 

A few notes:

Lion Geyser erupts in series of from one to eight eruptions.  The statistics shown are for the interval from the start of one series to the start of the next series.  The logger is not able to determine durations since the water column sprays in all directions and is not directly measurable.  Information about the number of eruptions is recorded (but not shown on the summary statistics table).

The very short minimum intervals for Plate Geyser are the result of interaction between nearby Boardwalk Geyser and Plate Geyser.  Sometimes when Plate starts just before Boardwalk, Plate stops its eruption once Boardwalk starts, then resumes about 15 minutes later.  The long intervals (4-5 hours) are also related to Boardwalk Geyser eruptions.