METO 200 WEATHER AND CLIMATE

 

                                                             DUE DECEMBER 20, 2011

 

PERSISTENCE THEOREM

 

The objective of this project is to determine whether the hypothesis of the persistence theorem is correct. Attached is a table with columns for the average wind speed, how much precipitation fell during the day, and the maximum, minimum and mean temperatures for the day. You will need two copies this table. All of the weather information can be obtained from the NWS web site:

                                    http://www.weather.gov/climate/index.php?wfo=lwx

            If you click on the URL above, it should lead you directly to the site.

            This web site is for Baltimore/Washington. Look under Observed Weather Reports

Then do the following:

(1)  Under Products click on ‘Preliminary Monthly Climate Data’

(2)  Under Location choose any site given

(3)  Under Timeframe click on Archived data and choose your favorite month

(4)  Under View click on GO

For the wind speed use the column marked AVG SPD. The max, min and mean (AVG) temperatures are in columns 2,3and 4.  For precipitation use column 7 (WTR).

 Use one of the sheets to record this information. You must record 28 CONSECUTIVE days.

To finish the project, now take the second sheet. Starting on the second day, compare the data for that day with that for the previous day, for the wind speed on the first sheet. If it is the same for both within the limits given below then mark the second sheet for the second day as ‘yes’, if it is outside these limits then mark it as ‘no’. Do this for each column on the sheet. Then move down to the next day and repeat the process.

The reason for the limits is that even within the same weather pattern there will be some variability for each of the parameters listed. We must allow for this in our experiment as we wish to clearly distinguish ‘changes’ in the weather. These limits are

 

WIND SPEED	5 MILES PER HOUR (OR KNOTS)
PRECIPITATION	ONE TENTH OF AN INCH
MEAN TEMPERATURE	5 DEGREES FAHRENHEIT
MAX TEMPERATURE	5 DEGREES FAHRENHEIT
MIN TEMPERATURE	5 DEGREES FAHRENHEIT

 

When you have finished analyzing the 28 days (27 days on the second sheet), count up the number of ‘yes’ and determine what fraction the ‘yes’ days are of the 28 days. To get full credit you must hand in the completed sheets for the 28 days, and a discussion of your results, for example, does your data support the persistence theorem. Please do not forget to put your name at the top of all the sheets that you hand in.

 

DAY	WIND SPEED	PRECIP, INCHES	MEAN TEMP	TEMP, MAX	TEMP, MIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28