Temperature Data
Three temperature probes made by Onset Computer Corporation (see the manufacturer's site for detailed information on the Optic StowAway temperature logger) were deployed in aquatic environments for the ecology study: one in Maunawili Stream at Maunawili Road, one in Omao stream at Maunawili Road, and one at the very upper end of the Oneawa Canal. In April 2000 these sensors were deployed in the late afternoon of April 14 and taken out after our study on April 18 (except the one in the Oneawa Canal, which could not be found until the morning of April 19 when the tide was again low). In May 2001, the sensors were placed in the same locations between the mornings of May 2 and May 4. The following chart shows the May 2001 recordings at all three locations:
What do the temperature recorders tell us about water temperature? Note, that all three show a pattern of rising temperature throughout the day, with a peak occurring late in the afternoon (as late as 5 pm in Oneawa Canal), followed by falling temperature through the night. Maunawili Stream below the road bridge reaches a higher temperature than nearby Omao Stream below the road bridge. Something strange happens in the Oneawa Canal. The temperature stops falling in the middle of the night (in April 2000 the water actually got warmer - see GRAPH)! How can this be explained?
The temperature results are summarized in the following tables:
| Location (2001) |
[mean temperature, st. dev., and range]
|
[data points & days] |
| Maunawili Str. |
26.96 oC +/- 0.97
|
24.8 - 28.9 oC
|
(193) ~ 2
|
| Omao Stream |
22.15 oC +/- 0.76
|
21.2 - 23.9 oC
|
(194) ~ 2
|
| Oneawa Canal |
22.52 oC +/- 1.11
|
21.3 - 25.8 oC
|
(194) ~ 2
|
| Location (2000) |
[mean temperature, st. dev., and range]
|
[data points & days] |
| Maunawili Str. |
21.35 oC +/- 0.54
|
20.7 - 23.2 oC
|
(371) ~ 5
|
| Omao Stream |
21.02 oC +/- 0.58
|
20.3 - 22.8 oC
|
(371) ~ 5
|
| Oneawa Canal |
22.97 oC +/- 1.21
|
20.4 - 24.5 oC
|
(451) ~ 6
|
How do the temperatures measured with the recording device compare with spot temperatures measured in the field? How do they compare with other windward streams?
Look for April 2000 or May 2001 summaries.
Water Quality Data
In addition to measurements made by the students in the field, water samples were collected in 2000 at two locations (Omao Stream and Upper Oneawa Canal) and analyzed by AECOS Inc. laboratory. These results are tabulated below. How do these values compare with those obtained in the field? Do you see any measurements that might not be working well in the field? Don't forget, some values could change between when these samples were collected and when you made the same measurements, so do not discard results that don't agree. You can track down more water quality results for these same streams by going to the KBAC website.
| Omao Stream at Maunawili Road |
|
|
|
|
pH |
Cond. |
Turb. |
|
NO2+ NO3 |
NH4 |
Total
N |
Total P |
LINKS |
|
No. |
Date |
Time |
|
umhos |
ntu |
/
| ug N/L |
ug N/L |
ug N/L |
ug P/L |
|
|
|
|
AE |
AE |
AE |
|
AE |
AE |
AE |
AE |
|
| |
---- |
04/18/00 |
0830 |
7.51 |
161 |
3.02 |
|
18 |
2 |
87 |
23 |
AE 12942 |
| Oneawa Canal (upper end) at Kaha Park |
|
|
|
|
pH |
Cond. |
Turb. |
|
NO2+ NO3 |
NH4 |
Total
N |
Total P |
LINKS |
|
No. |
Date |
Time |
|
umhos |
ntu |
/
| ug N/L |
ug N/L |
ug N/L |
ug P/L |
|
|
|
|
AE |
AE |
AE |
|
AE |
AE |
AE |
AE |
|
| |
---- |
04/18/00 |
0900 |
7.14 |
2670 |
11.4 |
|
2 |
4 |
492 |
102 |
AE 12942 |
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