Image Metadata File

Person Submitting Metadata/Point of Contact:

Name: Laura Stevens
Physical Address: 151 Patton Ave Asheville, NC 28801
Organization: CICSNC
Email:
Phone:

Image Info:

Image Title:
Time series of extreme precipitation index for the occurrence of 1-day, 1 in 5-year extreme precipitation
Image Description:
Time series of extreme precipitation index for the occurrence of 1-day, 1 in 5-year extreme precipitation, for the Northeast region. The dashed line is a linear fit. Based on daily COOP data from long-term stations in the National Climatic Data Center’s Global Historical Climate Network data set. Only stations with less than 10% missing daily precipitation data for the period 1895-2011 are used in this analysis. Events are first identified for each individual station by ranking all daily precipitation values and choosing the top N/5 events, where N is the number of years of data for that particular station. Then, event numbers for each year are averaged for all stations in each 1x1° grid box. Finally, a regional average is determined by averaging the values for the individual grid boxes. This regional average is the extreme precipitation index. There is no statistically significant trend.
Attributes (variables name, description and units):
Precipitation anomaly (/ year)
Temporal domain:
Start Time: 1895-01-01 00:00:00.0
End Time: 2011-12-31 00:00:00.0
Spatial domain:
Max latitude: 47.4375
Min latitude: 37.3125
Max longitude: -67.0625
Min longitude: -82.5625
Keywords:
Northeast, Observed, USGHCN Daily, Precipitation
Usage Limitations/Constraints:
Citation of image source:

Image Creation:

Who created the image:
Name: Laura Stevens
Physical Address: 151 Patton Ave Asheville, NC 28801
Organization: CICSNC
Email:
Phone:
When was image created (YYYY-MM-DD): 2012-08-15 00:00:00.0

Data Sources:

Dataset #1
Dataset Name: USGHCN Daily
Dataset Version:
Dataset Description: Global Historical Climatology Network - Daily
Dataset ID:
Dataset Release/Publication Date:
Affiliated Organization Name and Role: NOAA NCDC/Russ Vose
Date Accessed: 2011-06-06 00:00:00.0
Dataset Location (ftp, URL, etc): ftp://ftp.ncdc.noaa.gov/pub/data/ghcn/daily/
Data qualifier (QA/QC, etc):
The denominator of the scale of the source/output:
Spatial Reference system used by the source/output:
Citation to metadata:
Description of the scope of a resource, quality report, or process:
Spatial Extent of the source/output (polygon, box or region name): National
Temporal extent of the source/output: 1895-01-01 to 2011-12-31
Vertical extent of the source/output:
Identifier of the processing level of the source/input:
Spatial resolution of the source/output: 1 km

Processes:

Process #1
Input(s):
Step(s):
  • The data set is GHCN-Daily. Stations were selected by examining each station in the entire data base. Only stations with less than 10% missing daily precipitation data for the period 1895-2011 are used in this analysis. Days when the precipitation data had a quality flag were considered missing. Events are first identified for each individual station by ranking all daily precipitation values and choosing the top N/5 events, where N is the number of years of data for that particular station. A year was not included in this analysis if there were less than 300 non-missing precipitation values in that year. A day was excluded from being considered if the previous day?s value is missing; the purpose of this screen was to exclude possible precipitation values that may represent multi-day accumulations but are not flagged as such. After determining events for each station, event numbers for each year are averaged for all stations in each 1x1° grid box. Finally, a regional average is determined by averaging the values for the individual grid boxes. This regional average is the index.
Output(s):
Software:
Environment(s):
Additional Comments:

References: