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Assessment of impacts of climate change on water resources – a case study of the Great Lakes of North America
E. McBean,H. Motiee
Hydrology and Earth System Sciences Discussions , 2006,
Abstract: Historical trends in precipitation, temperature, and streamflows in the Great Lakes are examined using regression analysis and Mann-Kendall statistics, with the result that many of these variables demonstrate statistically significant increases ongoing for a six decade period. Future precipitation rates as predicted using fitted regression lines are compared with scenarios from Global Climate Change Models (GCMs) and demonstrate similar forecast predictions for Lake Superior. Trend projections from historical data are, however, higher than GCM predictions for Michigan/Huron. Significant variability in predictions, as developed from alternative GCMs, is noted. Given the general agreement as derived from very different procedures, predictions extrapolated from historical trends and from GCMs, there is evidence that hydrologic changes in the Great Lakes Basin are likely the result of climate change.
Assessment of impact of climate change on water resources: a long term analysis of the Great Lakes of North America
E. McBean,H. Motiee
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2008,
Abstract: In the threshold of the appearance of global warming from theory to reality, extensive research has focused on predicting the impact of potential climate change on water resources using results from Global Circulation Models (GCMs). This research carries this further by statistical analyses of long term meteorological and hydrological data. Seventy years of historical trends in precipitation, temperature, and streamflows in the Great Lakes of North America are developed using long term regression analyses and Mann-Kendall statistics. The results generated by the two statistical procedures are in agreement and demonstrate that many of these variables are experiencing statistically significant increases over a seven-decade period. The trend lines of streamflows in the three rivers of St. Clair, Niagara and St. Lawrence, and precipitation levels over four of the five Great Lakes, show statistically significant increases in flows and precipitation. Further, precipitation rates as predicted using fitted regression lines are compared with scenarios from GCMs and demonstrate similar forecast predictions for Lake Superior. Trend projections from historical data are higher than GCM predictions for Lakes Michigan/Huron. Significant variability in predictions, as developed from alternative GCMs, is noted. Given the general agreement as derived from very different procedures, predictions extrapolated from historical trends and from GCMs, there is evidence that hydrologic changes particularly for the precipitation in the Great Lakes Basin may be demonstrating influences arising from global warming and climate change.
Satellite Regional Cloud Climatology over the Great Lakes  [PDF]
Steven A. Ackerman,Andrew Heidinger,Michael J. Foster,Brent Maddux
Remote Sensing , 2013, DOI: 10.3390/rs5126223
Abstract: Thirty-one years of imager data from polar orbiting satellites are composited to produce a satellite climate data set of cloud amount for the Great Lakes region. A trend analysis indicates a slight decreasing trend in cloud cover over the region during this time period. The trend is significant and largest (~2% per decade) over the water bodies. A strong seasonal cycle of cloud cover is observed over both land and water surfaces. Winter cloud amounts are greater over the water bodies than land due to heat and moisture flux into the atmosphere. Late spring through early autumn cloud amounts are lower over the water bodies than land due to stabilization of the boundary layer by relatively cooler lake waters. The influence of the lakes on cloud cover also extends beyond their shores, affecting cloud cover and properties far down wind. Cloud amount composited by wind direction demonstrate that the increasing cloud amounts downwind of the lakes is greatest during autumn and winter. Cold air flows over relatively warm lakes in autumn and winter generate wind parallel convective cloud bands. The cloud properties of these wind parallel cloud bands over the lakes during winter are presented.
Regional impacts of ultrafine particle emissions from the surface of the Great Lakes
S. H. Chung, B. M. Basarab,T. M. VanReken
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2011,
Abstract: Quantifying the impacts of aerosols on climate requires a detailed knowledge of both the anthropogenic and the natural contributions to the aerosol population. Recent work has suggested a previously unrecognized natural source of ultrafine particles resulting from breaking waves at the surface of large freshwater lakes. This work is the first modeling study to investigate the potential for this newly discovered source to affect the aerosol number concentrations on regional scales. Using the WRF-Chem modeling framework, the impacts of wind-driven aerosol production from the surface of the Great Lakes were studied for a July 2004 test case. Simulations were performed for a base case with no lake surface emissions, a case with lake surface emissions included, and a default case wherein large freshwater lakes emit marine particles as if they were oceans. Results indicate that the lake surface emissions can enhance the surface-level aerosol number concentration by ~20% over the remote northern Great Lakes and by ~5% over other parts of the Great Lakes. These results were highly sensitive to the new particle formation (i.e., nucleation) parameterization within WRF-Chem; when the new particle formation process was deactivated, surface-layer enhancements from the lake emissions increased to as much as 200%. The results reported here have significant uncertainties associated with the lake emission parameterization and the way ultrafine particles are modeled within WRF-Chem. Nevertheless, the magnitudes of the impacts found in this study suggest that further study to quantify the emissions of ultrafine particles from the surface of the Great Lakes is merited.
Decadal Trends and Common Dynamics of the Bio-Optical and Thermal Characteristics of the African Great Lakes  [PDF]
Steven Loiselle, Andrés Cózar, Enyew Adgo, Thomas Ballatore, Geoffrey Chavula, Jean Pierre Descy, David M. Harper, Frank Kansiime, Ismael Kimirei, Victor Langenberg, Ronghua Ma, Hugo Sarmento, Eric Odada
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093656
Abstract: The Great Lakes of East Africa are among the world’s most important freshwater ecosystems. Despite their importance in providing vital resources and ecosystem services, the impact of regional and global environmental drivers on this lacustrine system remains only partially understood. We make a systematic comparison of the dynamics of the bio-optical and thermal properties of thirteen of the largest African lakes between 2002 and 2011. Lake surface temperatures had a positive trend in all Great Lakes outside the latitude of 0° to 8° south, while the dynamics of those lakes within this latitude range were highly sensitive to global inter-annual climate drivers (i.e. El Ni?o Southern Oscillation). Lake surface temperature dynamics in nearly all lakes were found to be sensitive to the latitudinal position of the Inter Tropical Convergence Zone. Phytoplankton dynamics varied considerably between lakes, with increasing and decreasing trends. Intra-lake differences in both surface temperature and phytoplankton dynamics occurred for many of the larger lakes. This inter-comparison of bio-optical and thermal dynamics provides new insights into the response of these ecosystems to global and regional drivers.
Agroecological distribution of banana systems in the Great Lakes Region
CA Eledu, EB Karamura, WK Tushemereirwe
African Crop Science Journal , 2004,
Abstract: Banana (Musa spp.) is important in the Great Lakes region of Africa as a staple food crop and source of income for the rural poor who also use it for various purposes; medicinal, cultural as well as industrial. The crop is grown across diverse agroecological conditions ranging from lowlands at sea level to highlands above 1500 m.a.s.l. Equally diverse are the socio-economic conditions associated with the crop across the region. The region is dominated both in production and acreage by the East African Highland bananas. Plantain and Cavendish production on the other hand dominate at the lower altitudes where the acreage under banana cultivation is steadily increasing. The agroecological diversity and the effects of socio-economic factors may have far-reaching implications to strategic planning for increased productivity of bananas especially considering possible effects on food security, pest/disease control, cultivar diversity and market/income. Using secondary information including existing databases on climate, land use/cover and edaphic factors, principal banana production areas have been mapped and an attempt made to overlay these with selected bio-physical and socio-economic factors in order to elucidate basic agroecological characteristics of these areas. The outcome clearly indicates that there exists potential for attaining food security and stable income, given the better climatic conditions prevailing, existing germplasm banks and near favourable accessibility. Opportunities and constraints based on climate, edaphic, human population densities and accessibility are recommended for further research and developments. KEY WORDS: Food security, geographic information systems (GIS), Musa spp., socio-economic factors RESUME La banane (Musa spp.) est importante dans la région des grands lacs comme nourriture de base et source des revenues pour les populations pauvres qui l'utilisent également pour d'autres buts, médical, culturel, et aussi bien qu'industriel. La plante est cultivée à travers diverses conditions agro écologiques des plaines aux hautes terres à 1500 m au dessus du niveau de la mer. Egalement diverses sont les conditions socio-économiques associées avec la plante à la région. La région est dominée en production et superficie par les bananes des hautes terres de l'Afrique de l'Est. La production de plantains et de Cavendish d'autre part est dominante dans les basses altitudes ou la superficie sous la banane est constamment croissante. La diversité agro écologique et les effets liés aux facteurs socio-économiques pourraient avoir entamé les stratégies de planification pour améliorer la productivité de la banane avec des effets sur la sécurité alimentaire, le contr le de pestes/maladies, la diversité des variétés et le marché/revenu. L'utilisation des données secondaires, la base des données climatiques existante, l'utilisation des terres/ couverture végétale et les facteurs locaux, les zones de productions de la banana ont été iden
Renegotiation of the 1987 Great Lakes Water Quality Agreement: From Confusion to Promise  [PDF]
Gail Krantzberg
Sustainability , 2012, DOI: 10.3390/su4061239
Abstract: For nearly four decades, the Great Lakes regime has invoked the Great Lakes Water Quality Agreement as the mechanism for binational cooperation on programs and policies. Many advances in water quality have led to unquestionable improvements in ecosystem quality, habitat and biodiversity, and water infrastructure. Still, Great Lakes scientists have issued compelling evidence that the ecological health of the basin ecosystem is at significant risk. In 2012, the Agreement will be revised for the first time in 25 years. The degree of engagement in a future Agreement, including scope, issues of significant importance, governance and collaboration will hinge on a thorough analytical process, so far seemingly absent, coupled with real consultation, so far marginally evident. Renegotiating the Agreement to generate a revitalized and sustainable future mandates that science inform contemporary public policy, and that inclusive discourse and public engagement be integral through the process. Many of these steps are still absent, and the analysis presented here strongly suggests that the constituents of the Great Lakes regime voice their views critically, emphatically, and often. If the negotiators listen, we can collectively make the Lakes Great.
Renegotiating the Great Lakes Water Quality Agreement: The Process for a Sustainable Outcome  [PDF]
Gail Krantzberg
Sustainability , 2009, DOI: 10.3390/su1020254
Abstract: This is a defining moment for the Great Lakes St Lawrence region, with the opportunity to renovate the regime for ecosystem improvement, protection and sustainability. The binational Great Lakes Water Quality Agreement was first signed in 1972. The outcome of a 2007 review of the Agreement by government and citizens, resulted in a broad call for and revisions to the Agreement, so that it can once again serve as a visionary document driving binational cooperation to address long-standing, new and emerging Great Lakes environmental issues in the 21st century. A prescription for renegotiating the Agreement to generate a revitalized and sustainable future mandates that science inform contemporary public policy, third Party Mediation presses for and coordinates a deliberate negotiation, and inclusive discourse and public engagement be integral through the process.
Interactive lakes in the Canadian Regional Climate Model, version 5: the role of lakes in the regional climate of North America
Andrey Martynov,Laxmi Sushama,René Laprise,Katja Winger
Tellus A , 2012, DOI: 10.3402/tellusa.v64i0.16226
Abstract: Two one-dimensional (1-D) column lake models have been coupled interactively with a developmental version of the Canadian Regional Climate Model. Multidecadal reanalyses-driven simulations with and without lakes revealed the systematic biases of the model and the impact of lakes on the simulated North American climate.The presence of lakes strongly influences the climate of the lake-rich region of the Canadian Shield. Due to their large thermal inertia, lakes act to dampen the diurnal and seasonal cycle of low-level air temperature. In late autumn and winter, ice-free lakes induce large sensible and latent heat fluxes, resulting in a strong enhancement of precipitation downstream of the Laurentian Great Lakes, which is referred to as the snow belt.The FLake (FL) and Hostetler (HL) lake models perform adequately for small subgrid-scale lakes and for large resolved lakes with shallow depth, located in temperate or warm climatic regions. Both lake models exhibit specific strengths and weaknesses. For example, HL simulates too rapid spring warming and too warm surface temperature, especially in large and deep lakes; FL tends to damp the diurnal cycle of surface temperature. An adaptation of 1-D lake models might be required for an adequate simulation of large and deep lakes.
Impacts of Mau Forest Catchment on the Great Rift Valley Lakes in Kenya  [PDF]
Mark Kipkurwa Boitt
Journal of Geoscience and Environment Protection (GEP) , 2016, DOI: 10.4236/gep.2016.45014
Abstract: Remote sensing and GIS applications are being widely used for various projects relating to natural resource management. Forests are very important national assets for economic, environmental protection, social and cultural values and should be conserved in order to realize all these benefits. Kenya’s forests are rapidly declining due to pressure from increased population, technological innovation, urbanization human development and other land uses. Mau forest is one of the major forests in Kenya that is a catchment area for many Great Rift Valley lakes within the country and faces a lot of destruction. Continued destruction of the Mau forest will cause catastrophic environmental damage, resulting in massive food crises and compromising the livelihoods of millions of Kenyans, and the possible collapse of the tourism industry. The purpose of this research was to investigate the relationship between the increasing rate of deforestation and the reduction of the volumes of water in the neighboring lakes between the years 1989 to 2010. Satellite images from Landsat-5 Thematic Mapper (TM) and Landsat-7 Enhanced Thematic Mapper (ETM+) were used for the detection of changes in the Mau forest and the dynamics of the neighboring water bodies that included lakes: Naivasha, Baringo, Nakuru, Elementaita and Bogoria. The research showed that from a period of 1989 to 2010 Mau forest has been decreasing due to deforestation and the water bodies have irregular dynamics in that, from 1989 to 2000, there was rise in the volume of water, this is attributed to the El Nino rains experienced in the country during the year 1997 and 1998. But between 2000 and 2010 the volume decreased as the forest is also decreasing. It is recommended that the government creates awareness to sensitize the public on the importance of such forests as catchment areas in Kenya.
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