DistPar

Contains parameters of the gamma and GEV distributions and the
 <code>Pr(Rain = 0)</code>, "probzero.rain".

datasets

A set of functions designed to calculate the standardised
precipitation and standardised precipitation evapotranspiration indices
using NASA POWER data as described in Blain et al. (2023)
<doi:10.2139/ssrn.4442843>. These indices are calculated using a reference
data source. The functions verify if the indices' estimates meet the
assumption of normality and how well NASA POWER estimates represent
real-world data. Indices are calculated in a routine mode. Potential
evapotranspiration amounts and the difference between rainfall and potential
evapotranspiration are also calculated. The functions adopt a basic time
scale that splits each month into four periods. Days 1 to 7, days 8 to 14,
days 15 to 21, and days 22 to 28, 29, 30, or 31, where 'TS=4' corresponds to
a 1-month length moving window (calculated 4 times per month) and 'TS=48'
corresponds to a 12-month length moving window (calculated 4 times per
month).

Gabriel Constantino Blain

PowerSDI

Calculate Standardised Drought Indices Using NASA POWER Data

Graciela R. Sobierajski

Leticia L. Martins

Adam H. Sparks

DistPar function

A <code>data.frame</code> with 13 variables and 48 rows.
<dl>
<dt>lon</dt>
<dd>longitude in decimal degrees</dd><dt>lat</dt>
<dd>latitude in decimal degrees</dd><dt>quart.month</dt>
<dd>The quartile of each month</dd><dt>alfa.rain</dt>
<dd>Shape parameter of the gamma distribution</dd><dt>beta.rain</dt>
<dd>Scale parameter of the gamma distribution</dd><dt>probzero.rain</dt>
<dd>Probability of rain=0</dd><dt>loc.harg</dt>
<dd>Location parameter of the GEV distribution, PE calculated by
 HS method</dd><dt>sc.harg</dt>
<dd>Scale parameter of the GEV distribution, PE calculated by HS
 method</dd><dt>sh.harg</dt>
<dd>Shape parameter of the GEV distribution, PE calculated by HS
 method</dd><dt>loc.pm</dt>
<dd>Location parameter of the GEV distribution, PE calculated by PM
 method</dd><dt>sc.pm</dt>
<dd>Scale parameter of the GEV distribution, PE calculated by PM
 method</dd><dt>sh.pm</dt>
<dd>Shape parameter of the GEV distribution, PE calculated by PM
 method</dd><dt>TS</dt>
<dd>Time scale at which the SDIs will be calculated</dd>
</dl>

Format

Parameters for Calculating the SDIs Provided by the ScientSDI Function — DistPar

A <code>data.frame</code> with 13 variables and 48 rows.
<dl>
<dt>lon</dt>
<dd>longitude in decimal degrees</dd>

<dt>lat</dt>
<dd>latitude in decimal degrees</dd>

<dt>quart.month</dt>
<dd>The quartile of each month</dd>

<dt>alfa.rain</dt>
<dd>Shape parameter of the gamma distribution</dd>

<dt>beta.rain</dt>
<dd>Scale parameter of the gamma distribution</dd>

<dt>probzero.rain</dt>
<dd>Probability of rain=0</dd>

<dt>loc.harg</dt>
<dd>Location parameter of the GEV distribution, PE calculated by
 HS method</dd>

<dt>sc.harg</dt>
<dd>Scale parameter of the GEV distribution, PE calculated by HS
 method</dd>

<dt>sh.harg</dt>
<dd>Shape parameter of the GEV distribution, PE calculated by HS
 method</dd>

<dt>loc.pm</dt>
<dd>Location parameter of the GEV distribution, PE calculated by PM
 method</dd>

<dt>sc.pm</dt>
<dd>Scale parameter of the GEV distribution, PE calculated by PM
 method</dd>

<dt>sh.pm</dt>
<dd>Shape parameter of the GEV distribution, PE calculated by PM
 method</dd>

<dt>TS</dt>
<dd>Time scale at which the SDIs will be calculated</dd>


</dl>

DistPar: Parameters for Calculating the SDIs Provided by the ScientSDI Function

Description

Usage

Arguments

Format

Examples