Getting WET in Arizona

Listening to the rain beat on my porch roof on Monday night brought reverential sighs of gratitude and more than one gentle-whispered "whoa" from every member of my household. If it had been a little bit warmer, there would have been at least one fairy-child out dancing in it. We are acutely tuned into rain around here.

The evening's down-pour also brought Nancy to my mind. She's my friend and co-worker, and she's also a Rainlogger. With her own two hands and dedication, she has recorded 10 inches of rain in the last 11 months, more now when we count Monday night's contribution.

The other day, Nancy pulled out her graph of rainfall at Maricopa County Cooperative Extension on Broadway and 43rd Street in Phoenix. There it was. A total of 10 inches had fallen, in the garden, right outside my office. The heaviest rain of the last 11 months had been July 13 when 2.05 inches fell in a single day. We had seen a three-month stretch of rainless days in the early spring, and then three months again in the late fall. Wow, who could argue with the data? But, it made me wonder, is 10 inches a lot of rain or a little?

I checked out the handy online Rainlog map only to find that there is a faithful Rainlogger close to my house. There, only 12 miles east of the office, that oh-so-rainy day in July had poured only 1.6 inches into a neighbor's rain gauge. But, the accumulated precipitation for the same time-period was very nearly equal to Nancy's. Curious! What about out in Glendale, near my sister-in-law's house? There, July 13 yielded only 0.6 inches of rain, but the total rainfall for the year was 12.5 inches. Why are the numbers so different? Human error and variations in people's dedication aside, the Rainlog map for July 13, 2008 showed me that a narrow storm has swept through the valley, released its burden over east Phoenix, and moved on. Folks to the west in Sun City and to the East in Apache Junction barely even got wet!

This Rainlog really is fun and entertaining! Not to mention quite a draw for citizen-scientists. And what a tool for teachers and students as well! This site has applications to data collection, data analysis, map-reading, graphing, and more. It opens doorways to math, science, and problem solving. It can start conversations around the dinner table or, over time, provide evidence for answers to deeper questions about climate change. And it all starts with a slim plastic rain gauge, a post in the ground, and a dedicated individual who is willing to record "zero" for days on end just to experience that thrilling occasion when there's actually cool, clear, water (or, warm, murky water, depending) in the bottom of the gauge.

Now, it's your turn. What could you discover at http://rainlog.org?

Looking for fabulous water-related educational materials? See Arizona Project WET at http://cals.arizona.edu/arizonawet/index.html