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Intermediate Stations Most information reported here has been from the longer-term consistently operating thermal monitoring stations, Other stations (Table 1) are in operation but have been excluded from this analysis due to insufficient or incomplete period of record, Some problems, such as exposure. to air, burial in sediment, loss, and malfunctioning instruments have been experienced, resulting in incomplete records at some loc/ltions. Other locations have been added recently and have been in operation for a short time, These stations provide important information on warming patterns within specific reaches of Grand Canyon. For example, Figure 9 shows mean daily temperatures during the period from June 1,2000 to August 1,2000 at four locations from just above the Little Colorado River at Mile 61 to the Grand Canyon gage near Phantom Ranch at Mile 87, The st3tions at Mile 65 and Mile 77 show that substantial warming occurs Mile 65, within the first four miles of the Little Colorado River, followed by a similar amount in the next eight miles at Mile 77. The remaining 10 mile reach to Mile 87 shows very little warming, The upper station is no doubt influenced by warm discharge from the Little Colorado River, as evidenced by a small discharge event during the first week. However, . the fact that the stations at Mile 65 and Mile 77 show most of the warming in that reach is most likely due to the openness of that reach below Marble Canyon and its north-south aspect, contrasted to the reach from Mile 77 to Mile 88, which is in the beginning of the Inner Granite Gorge, 11 18 (S' l ~ 18 I ~ ~14 j 13 12 OlJUNOQ OBJJNOQ lSJUNOQ WUNOO 29JJNOO Oe..lJLOO 1SJULOO IlOJULOO 27JULDI - 1'Oll1 - fIOllS - A077 - 1m7 Figure 9 Warming at iotermediate locations, LCR to Grand Canyon 10/25/00 DRAFT .'12