scholarly journals Periodic structures of Great Lakes levels using wavelet analysis

2011 ◽  
Vol 59 (1) ◽  
pp. 24-35 ◽  
Author(s):  
Taner Cengiz

Periodic structures of Great Lakes levels using wavelet analysisThe recently advanced approach of wavelet transforms is applied to the analysis of lake levels. The aim of this study is to investigate the variability of lake levels in four lakes in the Great Lakes region where the method of continuous wavelet transform and global spectra are used. The analysis of lake-level variations in the time-scale domain incorporates the method of continuous wavelet transform and the global spectrum. Four lake levels, Lake Erie, Lake Michigan, Lake Ontario, and Lake Superior in the Great Lakes region were selected for the analysis. Monthly lake level records at selected locations were analyzed by wavelet transform for the period 1919 to 2004. The periodic structures of the Great Lakes levels revealed a spectrum between the 1-year and 43- year scale level. It is found that major lake levels periodicities are generally the annual cycle. Lake Michigan levels show different periodicities from Lake Erie and Lake Superior and Lake Ontario levels. Lake Michigan showed generally long-term (more than 10 years) periodicities. It was shown that the Michigan Lake shows much stronger influences of inter-annual atmospheric variability than the other three lakes. The other result was that some interesting correlations between global spectrums of the lake levels from the same climatic region were found.

2000 ◽  
Vol 1 (4) ◽  
pp. 1
Author(s):  
Thorndike Saville, Jr.

The General Investigations program of the Beach Erosion Board comprises investigations, regional rather than local in scope, designed to improve, simplify, and expedite the solution of local problems, by giving a compilation of all existing data pertinent to shore processes in the particular region. As a first step in the compilation of these data, a study of wave and lake level conditions on the Great Lakes is being made. The results of such studies for Lake Michigan, Lake Erie, and Lake Ontario have recently been completed and published as Technical Memorandums of the Beach Erosion Board (Saville, 1953).


2021 ◽  
Author(s):  
Douglas A. Wilcox ◽  
John Bateman ◽  
Kurt Kowalski ◽  
James Meeker ◽  
Nicole Dunn

Abstract Water-level fluctuations are critical in maintaining the diversity of plant communities in Great Lakes wetlands. Sedge/grass meadows are especially sensitive to such fluctuations. We conducted vegetation sampling in a sedge/grass-dominated Lake Michigan drowned-river-mouth wetland in 1995, 2002, and 2010 that followed high lake levels in 1986 and 1997. We also conducted photointerpretation studies in 16 years dating back to 1965 to include responses to high lake level in 1952 and 1974. Topographic/bathymetric data were collected to assess their influence on areal extent of sedge/grass meadow. Dominant species in short emergent and submersed/floating plant communities changed with water availability from 1995 to extreme low lake levels in 2002 and 2010. Sedge/grass meadow was dominated by Calamagrostis canadensis and Carex stricta in all years sampled, but Importance Values differed among years partly due to sampling in newly exposed areas. Photointerpretation studies showed a significant relation between percent of wetland in sedge/grass meadow and summer lake level, as well as the number of years since an extreme high lake level. From the topographic/bathymetric map created, we calculated the cumulative area above each 0.2-m contour to determine the percent of wetland dewatered in select years following extreme high lake levels. When compared with percent sedge/grass meadow in those years, relative changes in both predicted land surface and sedge/grass meadow demonstrated that accuracy of lake level as a predictor of area of sedge/grass meadow is dependent on topography/bathymetry. Our results regarding relations of plant-community response to hydrology are applicable to other Great Lakes wetlands.


1971 ◽  
Vol 1 (3) ◽  
pp. 316-330 ◽  
Author(s):  
H. E. Wright

The intricate pattern of moraines of the Laurentide ice sheet in the Great Lakes region reflects the marked lobation of the ice margin in late Wisconsin time, and this in turn reflects the distribution of steam-cut lowlands etched in preglacial times in the weak-rock belts of gentle Paleozoic fold structures. It is difficult to trace and correlate moraines from lobe to lobe and to evaluate the magnitude of recession before readvance, but three breaks stand out in the sequence, with readvances at about 14,500, 13,000, and 11,500 years ago. The first, corresponding to the Cary advance of the Lake Michigan lobe, is represented to the west by distant advance of the Des Moines lobe in Iowa, and to the east by the overriding of lake beds by the Erie lobe. The 13,000-year advance is best represented by the Port Huron moraine of the Lake Michigan and Huron lobes, but by relatively little action to west and east. The 11,500-year advance is based on the Valders till of the Lake Michigan lobe, but presumed correlations to east and west prove to be generally older, and the question is raised that these and some other ice advances in the Great Lakes region may represent surges of the ice rather than regional climatic change. Surging may involve the buildup of subglacial meltwater, which can provide the basal sliding necessary for rapid forward movement. It would be most favored by the conditions in the western Lake Superior basin, where the Superior lobe had a suitable form and thermal regime, as estimated from geomorphic and paleoclimatic criteria. The Valders advance of the Lake Michigan and Green Bay lobes may also have resulted from a surge: the eastern part of the Lake Superior basin, whence the ice advanced, has a pattern of deep gorges that resemble subglacial tunnel valleys, which imply great quantities of subglacial water that may have produced glacial surges before the water became channeled.


2007 ◽  
Vol 135 (12) ◽  
pp. 4202-4213 ◽  
Author(s):  
Yarice Rodriguez ◽  
David A. R. Kristovich ◽  
Mark R. Hjelmfelt

Abstract Premodification of the atmosphere by upwind lakes is known to influence lake-effect snowstorm intensity and locations over downwind lakes. This study highlights perhaps the most visible manifestation of the link between convection over two or more of the Great Lakes lake-to-lake (L2L) cloud bands. Emphasis is placed on L2L cloud bands observed in high-resolution satellite imagery on 2 December 2003. These L2L cloud bands developed over Lake Superior and were modified as they passed over Lakes Michigan and Erie and intervening land areas. This event is put into a longer-term context through documentation of the frequency with which lake-effect and, particularly, L2L cloud bands occurred over a 5-yr time period over different areas of the Great Lakes region.


2009 ◽  
Vol 71 (3) ◽  
pp. 397-408 ◽  
Author(s):  
Andy Breckenridge ◽  
Thomas C. Johnson

AbstractBetween 10,500 and 9000 cal yr BP, δ18O values of benthic ostracodes within glaciolacustrine varves from Lake Superior range from − 18 to − 22‰ PDB. In contrast, coeval ostracode and bivalve records from the Lake Huron and Lake Michigan basins are characterized by extreme δ18O variations, ranging from values that reflect a source that is primarily glacial (∼ − 20‰ PDB) to much higher values characteristic of a regional meteoric source (∼ − 5‰ PDB). Re-evaluated age models for the Huron and Michigan records yield a more consistent δ18O stratigraphy. The striking feature of these records is a sharp drop in δ18O values between 9400 and 9000 cal yr BP. In the Huron basin, this low δ18O excursion was ascribed to the late Stanley lowstand, and in the Lake Michigan basin to Lake Agassiz flooding. Catastrophic flooding from Lake Agassiz is likely, but a second possibility is that the low δ18O excursion records the switching of overflow from the Lake Superior basin from an undocumented northern outlet back into the Great Lakes basin. Quantifying freshwater fluxes for this system remains difficult because the benthic ostracodes in the glaciolacustrine varves of Lake Superior and Lake Agassiz may not record the average δ18O value of surface water.


2020 ◽  
pp. 107-127 ◽  
Author(s):  
John D. Richards

Cahokia’s northern hinterland can be conceptualized as extending north from the central Illinois River valley into the western and upper Great Lakes region. The northern tier of this hinterland can be thought of as a region north of the Apple River area of northwest Illinois and south of a line extending east from the mouth of the St. Croix River to the western shore of Lake Michigan. This area includes a wide range of landscapes, biotas, and cultures and this diversity is mirrored in the Cahokia-related manifestations found throughout the region. This chapter provides a brief comparison of three northern tier sites/complexes including Trempealeau, Fred Edwards, and Aztalan in order to highlight the diversity of Mississippian-related occupations in the area.


1976 ◽  
Vol 33 (5) ◽  
pp. 1150-1155 ◽  
Author(s):  
Thomas M. Stauffer

I measured fecundity of coho salmon (Oncorhynchus kisutch) that matured in the Great Lakes to make comparisons with Pacific Ocean coho salmon and among groups of Great Lakes salmon. Numbers of eggs produced (1600–3500) by Great Lakes salmon were comparable to production (1500–3300) by Pacific salmon of similar size. Average egg diameters of Lake Michigan (7.1–7.4 mm) and Pacific salmon (6.1–7.4 mm) were also comparable but Lake Superior eggs were smaller (5.1–5.4 mm). Fecundity of second generation freshwater salmon which originated from Lake Michigan eggs was similar to that of the first generation which originated from Pacific eggs because the average numbers (2938–3243) and diameters (7.1–7.4 mm) of eggs produced were about the same. On the average, Lake Michigan salmon contained more (2938) and larger (7.1-mm diam) eggs than did Lake Superior salmon (2150 and 5.1-mm diam) of the same year-class and early life history.


1977 ◽  
Vol 34 (10) ◽  
pp. 1878-1889 ◽  
Author(s):  
J. C. Schneider ◽  
J. H. Leach

Changes in walleye (Stizostedion vitreum vitreum) stocks in the Great Lakes from 1800 to 1975 were linked to proliferation of foreign species of fish and culturally induced sources of stress — exploitation, nutrient loading, alteration of spawning habitat, and toxic materials. During the 1800s, three small spawning stocks (and probably many others) were damaged or destroyed because of either overfishing or elimination of spawning habitat through logging, pollution, or damming.During 1900–40, stocks in the Michigan waters of Lake Superior, southern Green Bay, the Thunder Bay River of Lake Huron, the North Channel of Lake Huron, and the New York waters of Lake Ontario declined gradually. Pollution, in general, and degradation of spawning habitat, in particular, probably caused three of the declines and overexploitation was suspected in two instances. In addition, the decline of three of these stocks occurred when rainbow smelt (Osmerus mordax) were increasing.During 1940–75, stocks in seven areas declined abruptly: Saginaw Bay (1944), northern Green Bay (1953), Muskegon River (mid-1950s), western Lake Erie (1955), Nipigon Bay (late 1950s), Bay of Quinte (1960), and Black Bay (mid-1960s). The decline of each stock was associated with a series of weak year-classes. The stocks were exposed to various sources of stress, including overexploitation, pollution, and interaction with foreign species, which, if not important in the decline, may be suppressing recovery. Only the western Lake Erie stock recovered, in part due to a reduction in exploitation and, possibly, because of the relatively low density of smelt and alewives (Alosa pseudoharengus) in the nursery areas.Relatively stable stocks persisted in five areas: Wisconsin waters of Lake Superior, Lake St. Clair — southern Lake Huron, eastern Lake Erie, northern Lake Huron, and parts of Georgian Bay. Pollution problems were relatively minor in these areas and exploitation was light during recent decades. Apparently these stocks were more capable of withstanding the additional stresses exerted by alien species. Key words: population fluctuations, Percidae, Stizostedion, Great Lakes walleye, history of fisheries, summary of stresses, harvests, management implications


1986 ◽  
Vol 43 (2) ◽  
pp. 407-415 ◽  
Author(s):  
Claire L. Schelske ◽  
Eugene F. Stoermer ◽  
Gary L. Fahnenstiel ◽  
Mark Haibach

Our hypothesis that silica (Si) depletion in Lake Michigan and the severe Si depletion that characterizes the lower Great Lakes were induced by increased phosphorus (P) inputs was supported by bioassay experiments showing increased Si uptake by diatoms with relatively small P enrichments. We propose that severe Si depletion (Si concentrations being reduced to ≤0.39 mg SiO2∙L−1 prior to thermal stratification) results when P levels are increased to the extent that increased diatom production reduces Si concentrations to limiting levels during the thermally mixed period. Large P enrichments such as those that characterized the eastern and central basis of Lake Erie and Lake Ontario in the early 1970s are necessary to produce severe Si depletion. It is clear that severe Si depletion in the lower lakes was produced by P enrichment because inflowing waters from Lake Huron have smaller P concentrations and larger Si concentrations than the outflowing waters of either Lake Erie or Lake Ontario. Severe Si depletion probably began in the 1940s or 1950s as the result of increased P loads from expanded sewering of an increasing urban population and the introduction of phosphate detergents. The model proposed for biogeochemical Si depletion is consistent with previous findings of high rates of internal recycling because, under steady-state conditions for Si inputs, any increase in diatom production will produce an increase in permanent sedimentation of biogenic Si provided some fraction of the increased biogenic Si production is not recycled or unless there is a compensating increase in dissolution of diatoms.


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