NOAA Technical Memorandum ERL GLERL-86 GREAT LAKES STATES MONTHLY PRECIPITATION DATA - BEGINNING OF RECORD TO 1990 Raymond A. Assel Cynthia E. Sellinger Don E. Meyer Raymond N. Kelly Great Lakes Environmental Research Laboratory Ann Arbor, Michigan February 1995 UNITED STATES NATIONAL OCEANIC AND Environmental Research DEPARTMENT OF COMMERCE ATMOSPHERIC ADMINISTRATION Laboratories D. James Baker James L. Rasmussen Ronald H. Brown Under Secretary for Oceans Director Secretary and Atmosphere/Administrator NOTICE Mention of a commercial company or product does not constitute an endorsement by the NOAA Environmental Research Laboratories. Use of information from this publication concerning proprietary products or the tests of such products for publicity or advertising purposes is not authorized. TABLE OF CONTENTS Page ABSTRACT ..............................................................................................................................................1 1. INTRODUCTION ................................................................................................................................1 2. METHODS ...........................................................................................................................................2 2.1 Equipment and Procedures . 2 2.2 Data ........................................................................................................................................2 2.3 Statistical Quality Control ......................................................................................................2 2.4 Examples of Data Inhomogeneities ........................................................................................ 4 3. RESULTS .............................................................................................................................................6 3.1 Computer File Documentation ...............................................................................................6 3.2 Precipitation Stations’ Spatial and Temporal Distribution Trends ......................................... 7 3.2.1 Period 1: 1817-1882 ......................................................................................................7 3.2.2 Period 2: 1883-1897 ......................................................................................................9 3.2.3 Period 3: 1898-1938 ......................................................................................................9 3.2.4 Period 4: 1939-1961 ...................................................................................................... 9 3.2.5 Period 5: 1962-1990 ...................................................................................................... 10 4. DISCUSSION .......................................................................................................................................12 4.1 Caveats on Data Usage . 12 4.2 Future Work ...........................................................................................................................12 . 5. ACKNOWLEDGMENTS ....................................................................................................................12 6. REFERENCES .....................................................................................................................................12 APPENDIX A: Listing of Stations Digitized by State ...............................................................................15 . 111 Figure la.-- Flow chart for scanning data ..................................................................................................3 Figure 1 b.-- Flow chart for processing scanned data .................................................................................3 Figure 2. -- Station 203940, Howard City, Michigan ................................................................................ 5 Figure 3. -- Station 20 1704, Coloma 3 NNW, Michigan ..........................................................................5 Figure 4. -- Station 4785 11, Tomah Ranger Station, Wisconsin ............................................................... 6 Figure 5. -- Stations with one or more months of data per year ................................................................ 8 Figure 6. -- Distribution of stations for period 1: 18 17- 1882 .................................................................... 8 Figure 7. -- Distribution of stations for period 2: 1883-l 897 .................................................................... 9 Figure 8. -- Distribution of stations for period 3 : 1898- 1938 .................................................................... 10 Figure 9. -- Distribution of stations for period 4: 1939- 196 1 .................................................................... 10 Figure 1 O.-- Distribution of stations for period 5: 1962- 1990 .................................................................... 11 TABLES Table l.-- Example of monthly precipitation summary . 7 iv ERRATA NOAA Tech. Mem. ERL GLERL-86 GREAT LAKES STATES MONTHLY PRECIPITATION DATA - BEGINNING OF RECORD TO 1990 p. iii Subheading 3.2.5 Period 5: 1962-1990 beings on page 11 p. 1 The second sentence in the second paragraph should be deleted: Discontinuities in the time series of each station’s monthly precipitation data are identified using a non-parametric test. p. 8 Figure 5, Number of Stations, the complete scale should read top to bottom: 2000 - 1500 - 1000 - 500 - O- GREAT LAKES STATES MONTHLY PRECIPITATION DATA - BEGINNING OF RECORD TO 19901 Raymond A. Assel, Cynthia E. Sellinger, Don E. Meyer, and Raymond N. Kelly ABSTRACT. Monthly precipitation data for 2,0 15 stations from begin- ning of record to 1947 for the eight Great Lakes states were digitized using an electronic scanner and optical character recognition software. These data were combined with digital monthly station precipitation data from 1948 to 1990 that was obtained from the National Climate Data Center (NCDC) in Asheville, North Carolina. The total number of stations in the combined data set is 3,447. Station latitude, longitude, elevation, and station name and changes in these metadata was also digitized. A complete list of stations is given as an appendix to the report. Data reduction, verification, quality control, and analysis methods are summarized. The spatial and temporal distribution patterns of the number of stations is presented. The digital data has been archived and is avail- able from NCDC in Asheville. 1. INTRODUCTION Much of the historical National Weather Service (NWS) precipitation data for the eight Great Lakes states prior to 1948 are available only in paper copy or microfiche, making them virtually unusable for most computer applications. The Great Lakes Environmental Research Laboratory (GLERL) developed a project, under the Environmental Research Laboratories Endangered Data and Increased Access Program and funded under the National Environmental Satellite and Data Information Service’s Earth System Data and Information Management Program, to make these data accessible for use in our own ongoing climate and lake hydrology related research programs, for use by other researchers, and for use by the public at large. Monthly precipitation data from 2,0 15 stations in Minnesota, Wisconsin, Illinois, Indiana, Michi- gan, Ohio, Pennsylvania, and New York were digitized from beginning of record to 1947. These data were quality controlled for data reduction errors and original data input errors (such as typographical errors but not for observer errors) and then combined with existing National Climatic Data Center (NCDC) digital monthly precipitation data from 1948 to 1990 for the states listed above. The total number of stations when including the 1948- 1990 period is 3,447. The station number and name, latitude, longitude, and elevation changes for each station were abstracted and digitized from NCDC state Summary of Station History forms (US Department of Commerce, 1956). The NCDC and state climatologists from several of the Great Lakes states provided important supplementary data and information that were helpful in the analysis of station changes and comparison data. Station history data reduction was completed under contract by NCDC as a GLERL-funded project. This report documents sources of the monthly precipitation data and describes procedures, equipment, and software used to abstract, reduce, and quality control these data. Discontinuities in the time series of each station’s monthly precipitation data are identified using a non-parametric test. The spatial and temporal distribution patterns of the precipitation stations are illustrated and discussed. A complete ‘GLERL Contribution No. 926 tabular summary of the monthly precipitation data at the 3,447 stations digitized for this study is not included with this report, but a listing of these stations is included along with their location (latitude, longitude, elevation) and period of record as Appendix A. A complete set of computer files of the precipi- tation data and station history data was provided to NCDC for archiving. 2. METHODS 2.1 Equipment and Procedures Digitization of published precipitation data was accomplished using an HP Scanjet II scanner that produced electronic image files. The computer image files were processed using Calera’s Optical Charac- ter Recognition (OCR) software that captured the character images and wrote them to a DOS ASCII file. That ASCII file was then edited using programs written