|Tuesday, June 01|
Stochastic Sequence Generation and Comparison for the Great Lakes Phase I Expedited Review
* Nicole O'Brien, Environment and Climate Change Canada , Canada
Frank Seglenieks, Canada
Laura Fagherazzi, Canada
André Temgoua, Canada
"The Great Lakes – St. Lawrence River Adaptive Management (GLAM) Committee was established in 2015 by the International Joint Commission (IJC). The GLAM committee is responsible for the ongoing evaluation of the IJC’s Great Lakes control board regulation plans, including Plan 2014. Plan 2014 is the regulation plan for determining the flows through the Moses-Saunders Dam, located on the St. Lawrence River between Cornwall, Ontario and Massena, New York. In response to public concerns over the management of Lake Ontario levels during extreme events in the past several years, the IJC have tasked the GLAM committee with completing an expedited review of Plan 2014. One of the goals of the expedited review is to determine appropriate deviations from Plan 2014 during high water events. The focus of this presentation will be on the generation of stochastic sequences used to support the first stage of the expedited review. Stochastic sequences were initially developed in 2005, whereas, the current analysis uses an updated period of record from 1900 to 2019. An overview of the methodology used to develop the stochastic sequences for Lake Ontario net basin supply (NBS) in 2005 and presently will be provided. Additionally, a comparison between the previous and present stochastic sequences will be discussed. "
Great Lakes response to structural changes in hydro-climate datasets
* André Temgoua, ECCC, Canada
Frank Seglenieks, Canada
"Over the last decades, a significant effort has been made by Environment and Climate Change Canada to understand the hydrodynamic of surface water flow through the Great Lakes. Structural changes in hydrometeorological datasets seem to be related to climate variability. There is also evidence of water levels fluctuations in relationship with weather events. Furthermore, the long-term impact of rising water levels on coastal areas could reshape the details of municipal maps and engender population displacements. Regional climate model (RCM) results are decisive in accurately simulating the unique nature of the Great Lakes given the large percentage of lake area in the basin. The climate simulations are based on CMIP5 scenarios driven by various members of the Coordinated Regional Climate Downscaling Experiment (CORDEX) for both the RCP4.5 and RCP8.5 scenarios. For this study, current and future climate simulations of temperature and precipitation are used to run the hydrological model WATFLOOD. The objective is to determine the potential relationship between extreme precipitation events and flooding. The results of the hydrological model are analyzed on a monthly basis in terms of differences between the current climate and future climate simulations. The hydro-climate variables investigated include temperature, precipitation, streamflow, snow water equivalent, evaporation, soil moisture, and Great Lake water levels. "
A Comparison among Tree-ring Reconstructed Warm and Cool Season Streamflow (1400-2018) for the North and South Saskatchewan River Sub-basins, Western Canada
* Samantha Kerr, University of Regina - Department of Geography and Environmental Studies, Canada
Yuliya Andreichuk, Canada
David Sauchyn, Canada
The North and South Saskatchewan River sub-basins comprise the Saskatchewan River Basin (SRB), which originates in the eastern slopes of the Rocky Mountains of Alberta (Canada) and Montana (USA), extending across the vast landscape of three Canadian Provinces. The SRB is the most populated region of the Northern Great Plains, where water demands from agriculture, industry, and municipalities can be a significant proportion of supply during periods of low flow and hydrologic drought. Changing climatic conditions, and shifts between periods of extreme wet and dry weather, emphasize the importance of a better understanding of past and future variability of the surface water balance within and between the sub-basins, as hydrological drought conditions occurring simultaneously can have detrimental effects for the region. Using a network of over 80 multi-species tree-ring chronologies, warm (May through August) and cool (December through April) season streamflow (1400-2018) were independently reconstructed for the North and South Saskatchewan River sub-basins. Departures from seasonal flow and spectral analyses of the reconstructions reveal significant modes of variability at inter-annual and multi-decadal scales, potentially related to the strong teleconnections between Pacific Ocean climate oscillations and the regional hydroclimatic regime.
Calibration of a semi-distributed coupled hydrological thermal model from satellite-based thermal imagery: Case study in Nunavik, Quebec
* Eisinhower Rincón, INRS, Canada
André St-Hilaire, Canada
Normand Bergeron, Canada
Stephen Dugdale, Canada
The most recent climate projections performed by the IPCC showed that Arctic and Subarctic regions would be affected by climate change stronger and faster than the rest of the world due to air temperature increases. This will have significant consequences for both environmental and human systems in Northern Quebec, particularly in the aquatic ecosystems of the region. Among those, fish habitats will be at risk. Species such as Atlantic salmon (Salmo salar) may be migrating further north, while others such as Arctic char (Salvelinus alpinus) may suffer from altered thermal regimes, which may reduce available habitat. The northern rivers have not been well studied by the scientific community because of the challenges associate with data gathering in the region. To our knowledge, discharge and temperature have been measured in only a few northern rivers in Canada, and data are limited to a few years of records. Given the paucity of data, hydrological thermal models become an essential tool to provide insights for present and future hydrological and thermal scenarios. This case study aims to understand the effects and risks of climate change on the Mélèzes River in Nunavik using novel techniques such as combining remote sensing data and water temperature modeling to overcome the information scarcity. We used CEQUEAU, a semi-distributed coupled hydrological thermal model that considers the basin's physical characteristics by subdividing it into elementary representative areas (ERA) and calculating the water balance and water temperature for each ERA through a production function and a heat budget, respectively. The water temperature data used to calibrate and validate the model were retrieved from Landsat 5, 7, and 8 missions through the Google Earth Engine platform calculated directly using a single-channel algorithm. These remote sensing instruments showed excellent results when used as input information to calibrate hydrological thermal models. For the first time, the CEQUEAU model was entirely calibrated using satellite-based thermal information. Results indicate that the Landsat missions are a good source of information to calibrate and validate the CEQUEAEU model and allow us to generate consistent historical daily time series of water temperature. Subsequently, the CEQUEAU model will be used to generate climate change scenarios and investigate possible hydro-thermal habitat changes for the two aforementioned species on the Mélèzes River watershed."
Streamflow trends or climate cycles in 50 years of SW Ontario stream gauge data
* Hida Manns, University of Guelph, Canada
Aaron A. Berg, Canada
Jaclyn Cockburn, Canada
" The global climate cycles manifest in cyclic changes in rainfall and temperature. These cycles can subsequently be seen in local weather patterns, lake levels and streamflow metrics. Data from the Hydat data base that was initiated to compare gauge station streamflow with rainfall in southern Ontario was observed to carry a short-term climate oscillation, of the timeframe of ENSO, and also a larger 30 year swing in trends over 50 years. In particular, the data questions if the minimum changepoint in runoff ratios in 1988 was a result of land use change and water absorption or a part of the larger climate cycle. Wavelet analysis will be applied to identify climate cycles to see if they are an integral part of the streamflow trends as well. This analysis will be helpful to separate the contribution of rainfall due to climate trends from changes in watershed absorption and to improve modelling of streamflow into the future. "