Solar Cycle 24 has officially started

4 01 2008

What a day! First a major storm whacks the west coast, now we have the official start of solar cycle 24.

Solar physicists have been waiting for the appearance of a reversed-polarity sunspot to signal the start of the next solar cycle. The signal for the start of a new cycle is sighting a particular kind of sunspot. That wait is over.

reversed_sunspot_010408.jpg
Click for larger image

A magnetically reversed, high-latitude sunspot, dubbed as number 981, emerged on the surface of the sun today. Just a few months ago, an “All Quiet Alert” had been issued for the sun. This reversed polarity sunspot today marks the beginning of Solar Cycle 24 and the sun’s return back to Solar Maximum.

Solar Cycle 24 has been the subject of much speculation due to competing forecasts on whether it will be an highly active or a quiet low cycle. If it is a low cycle, it may very well be a test of validity for some CO2 based AGW theories. Only time will tell.

UPDATE: There have been some questions about solar cycle length, and “when does one cycle end and another begin or is there overlap”? Thanks to Joe D’Aleo of ICECAP, please see the graph below:

solar_cycle_length.png

This from ESA may help everyone understand the transition:

With the next solar cycle this [sunspot magnetic] orientation is flipped in both hemispheres, as the Sun’s global magnetic field reverses its orientation.

As a new cycle begins, the number of sunspots with the reverse orientation will increase and the ones with the orientation of the old cycle will decrease in number. In the transition period they can both occur on the Sun, as the two cycles have no sharp boundary and overlap.

Russ Steele has some interesting information on the current state of knowledge and predicting the next solar cycle intensity at his Dalton Minimum Returns site.





Today’s storm is a 9.0

4 01 2008

A meteorologist friend of mine, Jan Null, has been keeping tabs on Winter Storms for some time. He’s developed something called the Bay Area Storm Index (BASI) which he uses to calculate the intensity of the storm by combining susatined wind, peak gusts, and rain totals. By his reckoning, this storm today rates a 9.0 on a scale of 1-10.

This is based on:

SF Downtown Rainfall = 2.01 as of 2 PM   (see http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=&sid=SFOC1&num=48 )

SFO Max Sustained Wind = 46kts at 1559Z = 53 mph at 7:59 AM  (see http://www.wrh.noaa.gov/mesowest/getobext.php?wfo=mtr&sid=KSFO&num=48&raw=1&dbn=m)

Max Gust Below 1500’= Angel Island  76 kts at 2009Z = 87 mph at 12:09 PM (see http://www.wrh.noaa.gov/mtr/versprod.php?pil=OMR&sid=DAR)

That makes this the strongest storm since a 9.0 December 16, 2002 and only the 12th storm of 9.0 or greater since 1950.  See the BASI archive  http://ggweather.com/basi_archive.htm

Locally in Chico as of 3PM we have 1.74 inches of rain from this storm, sustained winds of 41mph, and a peak wind of 66mph.

In Redding, Shasta Dam had 4.92″ of rain, with Redding Fire Station at 1.56 inches. Peak wind gust was 82 mph!

Above Paradise, Stirling City got 6.82 inches of rain in the last 24 hours and its still coming down. They’ll likely see it go beyond 7 inches in 24 hours with a storm total about 10 inches.
 





Mother Nature Whacks West Coast

4 01 2008
sat_pacific_010408.jpg
Click image for latest animation

UPDATE: For a high resolution still image of this “beautiful” storm click this link: pacific_nhemi_01-04-08_1430utc.jpg

The Friday storm moving into California is one of the strongest I’ve seen in about five years. The record rainfall for today in Chico, CA was 2.66 inches in 2002. The important thing to remember is this: Weather events like this are not individually attributable to climate change. We’ve had stronger storms before, and this one is about an 9.0 on a winter storm scale of 1-10. That makes this the strongest storm since a 9.0 December 16, 2002 and only the 12th storm of 9.0 or greater since 1950.  See the BASI archive  http://ggweather.com/basi_archive.htm  (h/t Jan Null)

Wind gusts so far have hit 66 mph according to Chico Airport, and 82 mph at Redding. Stronger wind gusts were in mountain passes. Note that hurricane force winds are categorized as being in sustained winds in excess of 74 mph.

To track this storm in real time, see my website at www.KPAY.com and click on the weather link for live doppler radar.

If you want a desktop doppler weather radar application, see my www.stormpredator.com website and download a copy.

This storm will be abating by about 5PM today.

WIND GUSTS REPORTED OVER INTERIOR NORTHERN CALIFORNIA THROUGH 10
AM…

SITE                           WIND GUST             TIME    
SUGARLOAF RAWS………………78 MPH…………..651 AM
PIKE COUNTY LOOKOUT RAWS……..67 MPH…………..710 AM
SACRAMENTO INT`L AIRPORT……..66 MPH…………..753 AM
MARYSVILLE………………….61 MPH…………..802 AM
SACRAMENTO EXEC AIRPORT………69 MPH…………..825 AM
BLUE CANYON…………………65 MPH…………..828 AM
BEALE AFB…………………..69 MPH…………..828 AM
ELK GROVE…………………..71 MPH…………..838 AM
SUISUN CITY…………………60 MPH…………..838 AM
STOCKTON……………………60 MPH…………..838 AM
REDDING…………………….82 MPH…………..849 AM
CHICO………………………66 MPH…………..855 AM
EAGLE PEAK RAWS……………..65 MPH…………..915 AM
LYONS VALLEY RAWS……………73 MPH…………..917 AM