Snow in Phoenix

This morning while I was in church, it was snowing. I live in Phoenix, Arizona. This is the third time this season that I've seen snow (or have had friends tell me about snow) in central Arizona. Last fall, I told my daughter that it was highly unlikely that we would ever see snow in Phoenix, unless we went into another little Ice Age. Seeing snow for the third time this season in a place that almost never gets snow, I'm beginning to wonder whether we are entering another Little Ice Age, or at least a period of cooling.

Snow in Phoenix During the Winter of 2010-2011

The Snow of 27 February 2011 is the third time that I've seen or heard reports of snow this season. The first time that it snowed this season was on December 30th. My friend saw this snow; in the place that I live, we see a lot less precipitation than my friends several miles north of me, so it was cold, but nothing fell from the sky. The second time that it snowed this season I only saw a few tiny flakes. Today, it snowed enough to cover the cars, although it melted fairly quickly.

Technically, the snow that fell was actually called graupel, which is like a soft form of hail, but in Phoenix, that's close enough to snow for us. People were actually throwing snowballs during the handshaking time at my church, when many of us went out to look at the weather.

Historical Snow in the Southwest

In the past 120 years, snow has been extremely rare. It has snowed less than 10 times since 1896, including graupel. Prior to 1896, snow was not officially recorded, but there was a time before weather records were kept that it did snow. While I was conducting research on the Little Ice Age, I did run into passages where people were travelling in the Southwest and had to deal with snow in the desert; snow covered cacti at the time. More than likely, it snowed several times during this time period. In 1816, it snowed in New England in June; the whole northern hemisphere was racked with extreme cold; people named that summer "A Year Without a Summer"; it probably snowed in Phoenix that year. The Little Ice Age ended in the 1860s.

The Role of Sunspots and Weather

In my research on the Little Ice Age, I have discovered that some of the coldest weather has occurred during periods where there was little sunspot activity. There was little sunspot activity during the two coldest periods of the Little Ice Age. During the late 1990s and early 2000s, when everybody was getting concerned about global warming, sunspots were up. Sunspots typically run in 11 year cycles, with the highest numbers of sunspots in the middle of the cycle. In the year 2000, close to the peak of the last cycle, there were only two months when the sunspot number went under 100, and then they were still in the 90s. We are currently nearing the peak of the next sunspot cycle. January 2011 was the 37th month of sunspot cycle 24, and had a sunspot number of 19. At month 37 in sunspot cycle 23 (May 1999), sunspots were dramatically higher, with a sunspot number of 106.4. We are clearly not seeing the sunspot numbers that we saw a decade ago.

Are we entering another Little Ice Age? There's no way to tell. Some people in the media will tell you that the cold weather we are experiencing is a result of global warming. Even my four-year old has more sense than that. For all we know, the weather could increase next year and leave us with record heat. All I know is, for now, it's pretty cold in Phoenix, and I kinda like snowballs (every once in a while).

Sources:

Brooke Lorren. Sunspots and Global Cooling. Squidoo.

Sunspot Data. Nasa.

Phoenix, Arizona. Wikipedia.

Year Without a Summer. Wikipedia.