4f071049-nca3-ghcn-daily-r201305-process

Decadal average anomalies for the number of 2-day, 5-year precipitation events (difference between the decade and the 1901-1960 average precipitation) for the contiguous U.S. were plotted as a bar graph. Note: the far right bar contains data for 12 years (2001-2012).

First, COOP stations with less than 10% missing daily precipitation data for the period 1901-2012 were identified. For each station, the accumulated precipitation values for 2-day periods were determined and then ranked for the entire period of record. Next, the top N values were identified, where N equals the number of years of available data, divided by 5. These events were considered extreme. Then, the number of extreme events in each year was computed. Next, grid box average values were calculated for each year, by averaging the values for each station available in that grid box. The annual values were then averaged for all grid boxes containing data in the contiguous U.S.. Decadal averages were then calculated. Finally, the 1901-1960 average value was subtracted from the decadal average value, and a percentage change was calculated.

The duration of this activity was 6 hours.

Output artifacts generated by this activity :

prcpextremes_2dy_5yr_19012012_May01_2013.txt
getprcpextremes_May01_2013.f95
gridaverage_May01_2013.f95
gridprcpextremes_2dy_5yr_19012012_May01_2013.txt
CS_gridprcpextremes_2dy_5yr_19012012_May01_2013.xlsx
CS_extreme precip index_13263_V9.png

This activity resulted in the following :

• image 4f071049-4952-4e2b-ac40-9942a7752382 was derived from dataset Global Historical Climatology Network - Daily

Computing environment : Linux (CentOS release 6.4); Mac OS X (darwin x86_64 m64)

Software used : Fortran 95; lf95 compiler (Lahey/Fujitsu Linux64 Fortran compiler release L8.10b); Microsoft Excel for Mac 2011 Version 14.3.9 (131030)

Visualization software used : Microsoft Excel for Mac 2011 Version 14.3.9 (131030)

Notes : Fortran 95 was used to perform numerical calculations. Microsoft Excel was used to perform averaging and to visualize the data.