Carbon Monoxide from a Freeway

Keywords: multiple regression, daily trend, harmonics.
Description

Hourly carbon monoxide (CO) averages were recorded on summer weekdays at 
a measurement station in Los Angeles. The station was established by the 
Environmental Protection Agency as part of a larger study to assess the 
effectiveness of the catalytic converter. It was located about 25 feet 
from the San Diego Freeway, which in this particular area is located 
at 145 degrees north. It was located such that winds from 145 to 325 degress 
(which in the summer are the prevalent wind directions during the 
daylight hours) transport the CO emissions from the highway toward the 
measurement station. Aggregate measurements were recored 
for each hour of the day 1 to 24.

Hour 	- 	hour of the day, from midnight to midnight
CO 	- 	average summer weekday CO concentration (parts per million)
TD 	- 	average weekday traffic density (traffic count/traffic speed)
WS 	- 	average perpendicular wind-speed component,
wind speed x cos(wind direction - 235 degrees)

Hour	CO	Traffic	Wind
1	2.4	50	-0.2
2	1.7	26	0.0
3	1.4	16	0.0
4	1.2	10	0.0
5	1.2	12	0.1
6	2.0	41	-0.1
7	3.4	157	-0.1
8	5.8	276	-0.2
9	6.8	282	0.2
10	6.6	242	1.0
11	6.6	200	2.3
12	6.3	186	3.8
13	5.8	179	4.6
14	5.5	178	5.4
15	5.9	203	5.9
16	6.8	264	5.9
17	7.0	289	5.6
18	7.4	308	4.9
19	6.4	267	3.8
20	5.0	190	2.5
21	3.8	125	1.4
22	3.5	120	0.6
23	3.3	116	0.4
24	3.1	87	0.1