Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields

Language:

Dates

Publication Date Range:

to

Document Data

Title:

Document Type:

Library

Collection:

Series:

People

Author:

Help
Clear All

Query Builder

Query box

Help
Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Regional Precipitation-Frequency Analysis and Spatial Mapping of 24-Hour Precipitation for Oregon [Report and Data files]

Filetype[PDF-1.57 MB]


  • English
    • Details Supporting Files You May Also Like

    Details:

    • Creators:
    • Corporate Creators:
      Oregon. Dept. of Transportation. Research Unit
    • Subject/TRT Terms:
    • Publication/ Report Number:
      OR-RD-FHWA-08-05
    • Resource Type:
      Tech Report
    • Geographical Coverage:
      Oregon
    • OCLC Number:
      742685369
    • Edition:
      Final report
    • Corporate Publisher:
      Oregon. Dept. of Transportation. Research Unit
    • NTL Classification:
      NTL-ENERGY AND ENVIRONMENT-ENERGY AND ENVIRONMENT
    • Abstract:
      For this study regional frequency analyses were conducted for precipitation annual maxima in the state of Oregon for the 24-hour duration. A total of 693 precipitation gages in Oregon, southern Washington, western Idaho, northern California and northern Nevada were included in the study, representing 34,062 station-years of record. A regional analysis methodology was utilized that pooled data from climatologically similar areas to increase the dataset and improve the reliability of precipitation-frequency estimates. The regional analysis methodology included L-moment statistics, and an index-flood type approach for scaling the annual maxima data. L-moment statistics were used to: characterize the variability, skewness and kurtosis of the data; measure heterogeneity in proposed homogeneous sub-regions; and assist in identification of an appropriate regional probability distribution.

      Spatial mapping techniques were employed for mapping of the precipitation-frequency information. This included spatial mapping of at-site means, L-moment ratio values of L-Cv and L-Skewness, and mapping of precipitation for selected recurrence intervals. Procedures were employed to minimize differences between mapped values and observed station values in a manner that was consistent with the regional behavior of the data and also recognized uncertainties due to natural sampling variability.

      Color-shaded isopluvial maps were developed for the 6-month, 2-year, 10-year, 25-year, 50-year, 100-year, 500-year, and 1000-year precipitation recurrence intervals. Electronic gridded datasets are available for use in creation of GIS applications that utilize precipitation-frequency information. Please see the "Supporting Files" tab for the zip of the data files.

    • Format:
      PDF
    • Funding:
      SPR 656
    • Collection(s):
    • Main Document Checksum:
    • Download URL:
    • File Type:

    You May Also Like

    Checkout today's featured content at rosap.ntl.bts.gov

    Version 3.26