Environmental Data Analysis BC ENV 3017
Lab: Esopus Creek, water quality - Part 3
The goal of the third
part of the lab is to look at some water quality parameters in the Esopus
Creek. Download the selected water quality
data from the web. The data are taken from a station on the Esopus Creek
(Shandaken), just upstream from the Coldbrook station (see map).
There are no water quality data for the Coldbrook station, however Coldbrook
has the longer record of discharge rates and therefore is better suited
for the 100y flood lab.
-
plot the discharge rate versus the day of the calendar year. How do you
explain this pattern?
-
plot temperature and O2 concentrations as a function of calendar day. Are
all the data of high quality?
-
the solubility of O2 in water depends on temperature. The table
below gives the concentration of O2 in equilibrium with the
atmosphere at sea level.
|
T(oC)
|
[O2] (mg/l)
|
|
0
|
14.6
|
|
5
|
12.8
|
|
10
|
11.3
|
|
20
|
9.1
|
|
30
|
7.5
|
|
40
|
6.4
|
-
Determine if there is a significant correlation between dissolved O2
and temperature.
-
Add the solubility data to your plot.
-
Can you explain the variability of the observed O2 concentrations
by variability in temperature only? How much of the variability is explained
by temperature?
-
Plot the timeseries and scatter plot of Na and Cl similar to O2
and temperature above.
-
How can you determine what the dominating species is that brings in Na
and Cl? (The atomic weights of Na are 23 and 35.45, respectively). Again,
how much of the variability can you explain?
-
Compare the average measured Na and Cl concentrations in the creek with
that in precipitation (Na,
Cl).
How do they differ and what could be the reason for the difference?
What should be in the lab report (Esopus Creek part 1-3)
-
some background information on drainage basin hydrology, why are we monitoring
streams?
-
in results section present discharge rate timeseries, the histograms and
normal distribution of the maximum discharge rate, as well as the water
quality plots
-
discuss any processes that might explain the trends that you see in the
discharge rates, the outcome of the 100y flood analysis, as well as the
water quality data.
-
We agreed that this lab report can be a bit shorter than the previous one.
Sources
