Use of Multiple Temperature Logger Models Can Alter Conclusions

Proceedings: Second Thermal Ecology and Regulation Workshop, 2008

Protection of aquatic life from hazardous extremes of temperature and markedly unnatural temperature changes has been a topic of regulatory concern since the 1950s. The history of efforts to regulate temperature has been one of changing perspectives and unresolved needs. This paper presents a brief account of this history to set the stage for the presentations and discussion in the Electric Power Research Institute's Second Thermal Ecology and Regulation Workshop.

Open-File Report, 2016

We constructed a one-dimensional daily averaged water-temperature model to simulate Trinity River temperatures for 1980-2013. The purpose of this model is to assess effects of water-management actions on water temperature and to provide water temperature inputs for a salmon population dynamics model. Simulated meteorological data, observed streamflow data, and observed water temperatures were used as model inputs to simulate a continuous 34-year time series of historical daily mean water temperature at eight locations along 112.2 river miles from Lewiston Dam near Weaverville, California, downstream to the Klamath River confluence. To demonstrate the utility of the model to inform management actions, we simulated three management alternatives to assess the effects of bypass flow augmentation in a drought year, 1994, and compared those results to the simulated historical baseline, referred to as the "No Action" alternative scenario. Augmentation flows from the Lewiston Dam bypass consist of temperature-controlled releases capable of cooling downstream water temperatures in hot times of the year, which can reduce the probability of disease outbreaks in fish populations. Outputs from the Trinity River water-temperature model were then used as inputs to an existing watertemperature model of the Klamath River to evaluate the effect of augmentation flow releases on water temperatures in the lower Klamath River. We structured the Trinity River water-temperature model in River Basin Model-10 (RBM10), which uses a simple equilibrium flow model, assuming discharge in each river segment on each day is transmitted downstream instantaneously. The model uses a heat-budget formulation to quantify heat flux at the air-water interface. Inputs for the heat budget are calculated from daily mean meteorological data, including net shortwave solar radiation, net longwave atmospheric radiation, air temperature, wind speed, vapor pressure, and a psychrometric constant needed to calculate the Bowen ratio. The modeling domain was divided into eight reaches ranging in length from 8.8 to 20.6 miles, which were calibrated and validated separately with observed water temperature data collected irregularly from 1980 to 2013. Root mean square errors of observed and simulated water temperatures for the eight reaches ranged from 0.25 to 1.12 degrees Celsius (°C). Mean absolute errors ranged from 0.18 to 0.89 °C. For model validation, a k-fold cross-validation technique was used. Validation root mean square error and mean absolute error for the eight reaches ranged from 0.24 to 1.11 °C and from 0.18 to 0.89 °C, respectively.

2000

Open-File Report, 2016

During summer 2014, lake level, streamflow, and water temperature in and around Crystal Springs Lake in Portland, Oregon, were measured by the U.S. Geological Survey and the City of Portland Bureau of Environmental Services to better understand the effect of the lake on Crystal Springs Creek and Johnson Creek downstream. Johnson Creek is listed as an impaired water body for temperature by the Oregon Department of Environmental Quality (ODEQ), as required by section 303(d) of the Clean Water Act. A temperature total maximum daily load applies to all streams in the Johnson Creek watershed, including Crystal Springs Creek. Summer water temperatures downstream of Crystal Springs Lake and the Golf Pond regularly exceed the ODEQ numeric criterion of 64.4 °F (18.0 °C) for salmonid rearing and migration. To better understand temperature contributions of this system, the U.S. Geological Survey developed two-dimensional hydrodynamic water temperature models of Crystal Springs Lake and the Golf Pond. Model grids were developed to closely resemble the bathymetry of the lake and pond using data from a 2014 survey. The calibrated models simulated surface water elevations to within 0.06 foot (0.02 meter) and outflow water temperature to within 1.08 °F (0.60 °C). Streamflow, water temperature, and lake elevation data collected during summer 2014 supplied the boundary and reference conditions for the model. Measured discrepancies between outflow and inflow from the lake, assumed to be mostly from unknown and diffuse springs under the lake, accounted for about 46 percent of the total inflow to the lake. Model simulations (scenarios) were run with lower water surface elevations in Crystal Springs Lake and increased shading to the lake to assess the relative effect the lake and pond characteristics have on water temperature. The Golf Pond was unaltered in all scenarios. The models estimated that lower lake elevations would result in cooler water downstream of the Golf Pond and shorter residence times in the lake. Increased shading to the lake would also provide substantial cooling. Most management scenarios resulted in a decrease in 7-day average of daily maximum values by about 2.0-4.7 °F (1.1-2.6 °C) for outflow from Crystal Springs Lake during the period of interest. Outflows from the Golf Pond showed a net temperature reduction of 0.5-2.7 °F (0.3-1.5 °C) compared to measured values in 2014 because of solar heating and downstream warming in the Golf Pond resulting from mixing with inflow from Reed Lake.

1999

In the summer of 1994 the Oregon Department of Forestry, in cooperation with Oregon State University's College of Forestry, conducted water temperature monitoring on a range of streams in the Coast Range and Interior georegions. The objectives were: 1) to characterize the variability in temperature patterns throughout a forested basin in mostly closed canopy conditions; 2) to collect preharvest water temperature data for a streamside alder conversion unit; 3) to examine water temperature patterns and downstream heating and cooling trends for small nonfish-bearing streams flowing out of clearcuts without tree retention; and 4) to use the water temperature data to field-check Oregon's proposed method for characterizing water temperature. Continuous water temperature thermographs were installed in the streams to record temperatures every 48 minutes during the summer months. Intensive monitoring was conducted on Brush Creek, a tributary to the Umpqua, a 13,000-acre watershed with significant populations of coho salmon, steelhead and cutthroat trout. Twenty-two thermographs were placed in Brush Creek's headwaters, main stem and major tributaries. Thermographs were also placed at seven other sites where streams were flowing through clearcut units. For most clearcut sites thermographs were installed just below the unit and at about 500 and 1200 feet downstream.

Water, 2015

Water temperature is a critical variable for water quality control and management. The primary objective of this paper was to develop and compare simple methods to estimate hourly water temperatures in rivers. The wave function (WF) model, originally used to calculate hourly air temperature, was modified and applied to eight Alabama rivers. The results show significant improvement by using the modified WF model instead of direct linear and non-linear (polynomial and logistic) regression models with time lags (4-5 h). The average Nash-Sutcliffe coefficient (NS) used to evaluate model accuracy for the eight rivers improved from 0.71 for the linear model to 0.89 for the modified WF model with NS for most rivers exceeding 0.90. A lumped modified WF model was also developed by combining water temperature data for all eight rivers and can be applied for rivers in Alabama when no observed water temperatures are available to develop a site-specific WF model. The procedure to develop a modified WF model can be applied to other regions.

Hydrological Processes, 2005

Thermochron iButtons incorporate the latest in digital technology, making them smaller, less expensive, durable and potentially more reliable than many other temperature logging devices. The objective of this study was to test the accuracy of an inexpensive air temperature measurement system, composed of a Thermochron iButton and radiation shield. Sixty-one iButtons were subjected to a sequence of two water baths (0°C and 24·9°C) to assess the absolute accuracy of the sensors. Five solar radiation shields were tested in a greenhouse setting to evaluate the reduction in radiative heating. Significant differences (p < 0·05) were detected between instruments subsequent to both water-bath treatment analyses. The accuracy of the sensors was well within the manufacturer's stated specification of ±1·0°C with a collective temperature variance of ±0·21°C. Temperature responses generated by the Thermochron iButtons in different radiation shields were consistent, but varied significantly (p < 0·05) from 28 to 44°C based on diurnal temperature ranges. Results indicate that the Thermochron iButton is an accurate, inexpensive alternative to more expensive temperature datalogging systems, and is well suited for obtaining quality spatially distributed data for hydrologic and water quality investigations.

An analysis of the relationship between air and stream water temperature records for 11 rivers located in the central United States was conducted. The reliability of commonly available water temperature records was shown to be of unequal quality. Simple linear relationships between air (Ta) and water (Tw) temperatures were developed for daily and weekly average temperatures and showed some level of accuracy, especially for weekly average temperatures and for small streams.

Hydrological Processes, 2014

Stream water temperature (t s ) is a critical water quality parameter for aquatic ecosystems. However, t s records are sparse or nonexistent in many river systems. In this work, we present an empirical model to predict t s at the site scale across the USA. The model, derived using data from 171 reference sites selected from the Geospatial Attributes of Gages for Evaluating Streamflow database, describes the linear relationship between monthly mean air temperature (t a ) and t s . Multiple linear regression models are used to predict the slope (m) and intercept (b) of the t a -t s linear relation as a function of climatic, hydrologic and land cover characteristics. Model performance to predict t s resulted in a mean Nash-Sutcliffe efficiency coefficient of 0.78 across all sites. Application of the model to predict t s at additional 89 nonreference sites with a higher human alteration yielded a mean Nash-Sutcliffe value of 0.45. We also analysed seasonal thermal sensitivity (m) and found strong hysteresis in the t a -t s relation. Drainage area exerts a strong control on m in all seasons, whereas the cooling effect of groundwater was only evident for the spring and fall seasons. However, groundwater contributions are negatively related to mean t s in all seasons. Finally, we found that elevation and mean basin slope are negatively related to mean t s in all seasons, indicating that steep basins tend to stay cooler because of shorter residence times to gain heat from their surroundings. This model can potentially be used to predict climate change impacts on t s across the USA. Figure 2. Location and characteristics of sites considered for monthly (left) and seasonal analyses (right). Bottom histograms present the distributions of drainage area and elevation. Reference sites are depicted in green (n = 171) and nonreference sites are depicted in red (n = 95). The histograms in the right correspond to those sites considered for the summer season analysis (n = 96) C. SEGURA ET AL.

Journal of the North American Benthological Society, 2010

Analyses of long-term data are an important component of climate-change research because they can help further our understanding of the effects of climate change and can help establish expectations for biological responses to future climate changes. We used macroinvertebrate data to assess whether biological trends associated with directional climate change could be detected in routine biomonitoring data from Maine, North Carolina, and Utah. We analyzed data from 8 long-term biomonitoring sites that had 9 to 22 y of data, and focused on thermal-preference metrics based on coldand warm-water-preference trait groups. The thermal-preference metrics were derived primarily from weighted-average or generalized-linear-model inferences based on data from each state database and are region specific. Long-term trends varied across sites and regions. At some sites, the thermal-preference metrics showed significant patterns that could be interpreted as being related to directional climate change, whereas at others, patterns were not as expected or were not evident. The strongest trends occurred at 2 Utah sites that had §14 y of data. At these sites, cold-water taxa were negatively correlated with air temperature, and, when years were grouped into hottest-and coldest-year samples, were strongly reduced in the hottest-year samples. Results suggest that thermal-preference metrics show promise for application in a biomonitoring context to differentiate climate-related responses from other stressors.