Table 2.

Estimates of time-integrated arithmetic average of different variables, mean and range of coefficient of variation (CV% = SD / mean × 100), and sample size necessary to detect a 5% change with a power of 80% and a significance level of 95% (α = 0.05; β = 0.2). Estimates based on the original values from 21 stations and 24 sampling occasions. “Over time” means that the parameters are based on the spatial average of the 21 stations at each sampling occasion, i.e., average of 24 CV% values. “Over stations” means that the parameters are based on the temporal average for each station over the 24 time points, i.e., average of 21 CV% values. “Normal” means that original data from each individual station and time point has been used, and “log-normal” means that log transformed data was used

Definition	Statistic	Salinity	Temperature	Ext. coeff.	Oxygen	CDOM	Chlorophyll
Over time
Normal	Average	3.90	11.23	0.78	90.57	4.89	2.68
	Mean CV%	16.18	46.21	25.82	4.18	50.63	29.51
	CV% range	13.78–29.84	43.28–49.76	17.58–44.03	2.44–5.52	36.35–88.57	17.41–45.61
	Sample size	15	669	211	8	806	275
Log-normal	Average	3.84	9.55	0.74	90.49	4.47	2.57
	Mean CV%	29.34	19.76	191.38	1.15	33.52	51.13
	CV% range	28.46–46.50	16.53–21.58	134–342	1.02–1.22	23.48–38.31	47.50–53.78
	Sample size	272	125	>10,000	3	355	822
Over stations
Normal	Average	3.90	11.27	0.78	90.87	4.87	2.72
	Mean CV%	6.24	3.68	24.42	1.26	24.23	12.52
	CV% range	1.59–18.47	0.68–9.88	11.66–63.68	0.38–3.93	3.38–110.66	2.80–37.65
	Sample size	85	7	189	3	187	52
Log-normal	Average	3.83	11.27	0.75	90.83	4.74	2.69
	Mean CV%	31.00	13.85	189.61	1.12	29.06	44.40
	CV% range	19.28–36.86	5.83–44.09	123–440	1.15–1.16	8.67–43.55	23.18–71.59
	Sample size	304	63	>10,000	3	267	621