Physical Sciences and Mathematics Commons^™

Colder By The Lake? The Lake Effect On Static Air Temperatures In Duluth, Minnesota 1961-1990, Graham A. Tobin, Gordon L. Levine, Jacqueline H. Alexander

Journal of the Minnesota Academy of Science

To test the impact of Lake Superior on local climates, daily temperature data were collected from two weather stations in Duluth, Minnesota for the period 1961 through 1990. The broad goal of the research was to ascertain to what extent climate conditions differed between lakeside and inland locations. Temperature data were standardized to local lake-level to control for altitudinal differences between weather stations. These data were then analyzed at two temporal scales, annual and seasonal, with the focus on mean high and mean low temperatures. Results indicated that the moderating effect of the lake indeed was apparent especially in raising …

The Importance Of Understanding Climate And The Use Of Climate Information, Stanley A. Changnon

Journal of the Minnesota Academy of Science

In this paper, the interrelated issues of understanding climate and its importance are addressed through consideration of three factors. Considered first are the general views of climate, as seen by three principal groups who deal with climatic conditions; the public, the weather-sensitive sectors, and the scientific community. The second consideration is how the atmospheric sciences community and climatologists specifically, have helped society function. Finally, activities and knowledge of climate which are changing over time, are assessed. I want to stress these are views· developed over 43 years as an atmospheric scientist. I have had the privilege of conducting a wide …

Sixty-Day Temperature Persistence At Five-Day Intervals For Minneapolis-St. Paul, Charles J. Fisk

Journal of the Minnesota Academy of Science

The annual course of 60-day temperature persistence for Minneapolis-St. Paul, Minnesota is examined at five -clay intervals for the last 110 years. Results show maximum persistence for the 60-day periods February 20 to April 20 and June 25 to August 23. Minimum persistence is observed for sequences whose midpoints correspond to late April, late September and mid-November. This suggests the presence of a single favored regime-breaking period for the winter to summer transition and two such periods for summer to winter.

A Technique For Collecting Water Samples Under Extreme Winter Conditions, J. B. Carlson, G. E. Ahlgren

Journal of the Minnesota Academy of Science

No abstract provided.

A Study Of Vertical And Horizontal Visibility Relationships Under Water, Jean J. Mccarthy

Journal of the Minnesota Academy of Science

A threefold study was undertaken to:

1) determine the nature of the mathematical relationship between vertical and horizontal visibility underwater

2) examine the feasibility of using the Secchi disc method to measure horizontal visibility in the photic zone;

3) obtain descriptive data on vertical and horizontal visibility in selected lakes of southern Minnesota.

The Secchi disc technique for measuring· visibility was modified to accommodate horizontal readings, and data were col1lected from 12 lakes at 5, 15 and 25 feet depths under controlled conditions. Reliability correlations were significant (p ( .01) and ranged from .764 to .994. Correlations and regression equations …

Successive Month Temperature Relationships For Twin Cities, 1820-1974, Charles J. Fisk

Journal of the Minnesota Academy of Science

Using a five category classification scheme of mean monthly temperatures, the long-term ( 1820-1974) relationships between Minneapolis-St. Paul successive months' temperatures were analyzed . Results show predominance of two-month persistence over two-month breaks in classification . Strong above norma11 and below normal persistence tendencies are revealed, particularly in summer and early fall sequences. In contrast, two month breaks in classification appear in spring and fall sequences. This emphasizes the uneven progression of warming (cooling) that occasionally occurs between winter (summer) and summer (winter). Overall, strongest month-to-month association was for August-September, weakest for April-May .

Annual Precipitation Regime Of Minnesota, Richard H. Skaggs

Journal of the Minnesota Academy of Science

Eigenvalues and eigenvectors computed on 30-year normals indicate an unusually high spatial homogeneity of annual precipitation curve shape in Minnesota. The generalized shape accounts for about 99 per cent of the observed variance and meshes well with the overall pattern of the central United States. Interesting deviations do occur, however. These deviations suggest fundamental questions about precipitation-causing processes which should be investigated in the future.

Morphology And Water Quality In Three Abandoned Granite Quarries, Keith M. Knutson

Journal of the Minnesota Academy of Science

Limnological conditions were studied in two abandoned granite quarries in George Friedrich Park, St. Cloud, Minn. These quarries were excavated from 1886 to 1890 and left shallow due to inadequate water pumping systems at the time. The quarries were less than one hectare in area and had mean depths of 7.3 and 8.2 m. The annual heat budget was about the same for both quarries, 10,535 gm. cal/cm•. Concentrations of [chemical symbols] were determined. Very low concentrations of nitrate nitrogen were found ([chemical symbols]). The hypomimia of both quarries contained hydrogen sulfide throughout the study. Data show West Quarry to …

A Comparison Between The Direction Of Tornado Movement And The Associated 500 Mb. Level Wind Direction, Allen B. Johnson

Journal of the Minnesota Academy of Science

An investigation to ( 1) determine the 500-milli-bar level weather patterns associated with tornadoes moving from northwest toward southeast and from southwest toward northeast and, (2) show the significance of the contrasts between the 500-mb. level weather patterns of the two tornado types. A very high relationship between the direction of the 500-mb. level winds and the tornado direction was substantiated by a coefficient of correlation of +0.88. The typical 500-mb. level low center associated with the northwest to southeast type tornado was located over Hudson Bay about 1300 miles north-northeast of the tornado area. The low center associated with …

Some Recent Advances In Meteorology, Erwin E. John

Journal of the Minnesota Academy of Science

No abstract provided.

Droughts, Dust Storms And Desolation, D. H. Davis

Journal of the Minnesota Academy of Science

No abstract provided.

Meteorological Statistics, William Cheney, T. S. Outram

Journal of the Minnesota Academy of Science

No abstract provided.

Meteorological Statistics, William Cheney

Journal of the Minnesota Academy of Science

No abstract provided.

An Account Of The Tornado Which Visited Saint Cloud, Minnesota, April 14, 1886, C. W. Hall

Journal of the Minnesota Academy of Science

No abstract provided.

High Water At Mankato, 1881, M. B. Haynes

Journal of the Minnesota Academy of Science

No abstract provided.

Meteorological Statistics, William Cheney

Journal of the Minnesota Academy of Science

No abstract provided.

Notes On A Hail Storm, Occurring August 18th, 1858, Nathan Butler

Journal of the Minnesota Academy of Science

No abstract provided.

Tornadoes And Cyclones, T. L. Rosser

Journal of the Minnesota Academy of Science

No abstract provided.

Notes Of A Remarkable Storm, George B. Wright

Journal of the Minnesota Academy of Science

No abstract provided.

Meteorological Statistics, William Cheney

Journal of the Minnesota Academy of Science

No abstract provided.