176
TABLE 63. SrratiricaTion TaBuLaTion Prepiction TEcHNIQUE BanpDs FOR Wixp Direction AND Hour or Day
|
|
number
Winddirection, degrees
I
iI
55-105
205-355
5-15
115-195
2
15-135
275-355
145-265
5
| 914!
1-8
15-24
3
355
5-195
205-345|
, 220)
1
21-24
4
5-135
145-265
275-325;
1-4
165-205
245-255
45-95
135-155
5-45
105-125
1-3
5-6
15-55
5
145-285 295-325
335-345 355
65-135
1
6
7
8
335-355
215-235
265-355
|
III
Hour (CST)
or
TAM
station
25-45
1
| ou | III
1-2
t-17
18-24 |
j
9-10}
12-24
APPLICATION
OF
5-35
75-125 |
315-355
TABULATION
1-6
11-15;
17-24
PREDUCTION
used because of the developmental nature of this
work; but a municipality may use this form as a guide
in tailoring one to its own needs. The symbol Prb
stands for the probability estimate of the forecast
verification.
|
17-24
4
7-8
After the forecast values are received, a clerk
may use the 50 percentile entry of the Tabulation
Preduction Scheme Tables to enter the predicted
SOs concentration or those of another pollutant of
interest and present these to the meteorologist.
Ordinarily, municipal air pollution control agencies
1
1-7 14-22)
23-24
5-65 225-265 75-215) 24
275-325 335-345
355
|
45-65
135-305
5-16
3-5
in Figure 138, This form has been in use in test operations with Murray and Trettel, Inc. providing the
hourly forecasts and the Argonne National Laboratory and the City of Chicago Department of Air Pollution Control adapting the forecasts for operational
use,
More variables are indicated than were actually
will find it uneconomical to employ a complete forecasting staff. Hourly forecasts will, therefore, be ob-
8-13
of one or two meteorologists employed by the air pollu-
1
10-16
5-9 19-22
17-18
23-24
7-10
16
SCHEME
tained from an organization like the U. 8. Weather
Bureau or a private meteorological firm. The services
TO
tion control agency would be used to interpret the
forecasts of both the weather and pollutant concen-
tration for action by appropriate officials.
The
municipal
meteorologist
would
determine
whether an air pollution incident was probable
within the forecast period. His access to the latest
upper air and surface weather charts enables him to
judge whether (1) a land-sea breeze will develop,
(2) a thunderstorm is likely, (3) precipitation or fog
will appear, (4) a frontal system will pass, or (5)
DAILY OPERATIONS
Since the variables used in the Tabulation Pre-
diction Scheme are wind direction, wind speed,
temperature, ceiling heights, and hour of day,
these are the variables (except of course the hour of
day) for which forecasts are required. The forecasts
should be made for each hour and the range of the
group interval, e.g., a wind speed forecast over the
range of 4-7 miles per hour, should correspond to
the ranges in the Tabulation Prediction Scheme.
The forecast for the day should preferably be made
between 0700 and 0800 so that the severity of the
early morning pollution peak will be covered. Forecasts for 12 to 24 hours are reasonably routine. These
forecasts may be issued every 6, 12, or 24 hours, depending on the local needs. Of course, during potential or actual severe pollution conditions, constant
surveillance is necessary.
A format for recording the forecasts and the com-
puted and observed pollution concentrations is shown
TABLED 64. Units anp Group INTERVALS FOR VARIABLES
USED IN THE TABULATION PREDICTION SCHEME
1. Wind speed
Unit: miles per hour
Group interval: 0-3, 4—7, 8—12, 13—18, 19—24, >24
2. Wind direction
Unit: degrees
Group interval: 10-degree grouping : 5—14, 15—24, 25—35,
ete., or aceording to band widths of
Table 63.
3, Temperature
Unit: °F
Group interval: —20— —11, —10—-—1, 0—-9, 10—19,
20-29, 30-39, 40—49, 50—59, 60—69,
70—79, 80-89, 90—-99
4. Ceiling height
Unit: feet
Group interval: 0—-999, 1000—2499, 2500—6999, > 7000
5. Hour of day
Unit: one hour
Group interval: one hour intervals centered on the hour;
or according to band width of Table 63.