/IMD_rainfall_IDW

An Exploratory Analysis of the Monsoon season in several Indian districts

Primary LanguageR

Rainfall and Temperature Trends during India's Monsoon Season

The code in this repository formed part of my application for a research position. I was asked to clean and explore a partially cleaned large dataset, millions of observations across five variables, from the Indian Meteorological Department. The individual datasets making up the larger dataset contained grid-point data on daily rainfall/temperature from 2009-2013. Each grid point came from a 1◦(latitude) by 1◦(longitude) grid covering the Indian subcontinent.

Data Cleaning

The primary sub-task of the data cleaning step involved collapsing the grid-level dataset into a district-level dataset.

I was given an algorithim to match each grid point to a district and expected to operationalize that using my chosen coding language. The algorithm to match each grid point to a district was as follows:

  1. Take a weighted average of daily mean temperature, daily mean rainfall, and daily total rainfall for all grid points within 100 KM of each district’s geographic center.
    • The weights are the inverse of the squared distance from the district's center.
    • A district crosswalk dataset had data on the district centroids for the five Indian states I was expected to focus on.

To determine which grid points lay within 100 KM of each district center, I also had to calculate the distance between every grid point and every centroid.

Data Exploration

The primary sub-task of the data exploration step involved using the district-level dataset from the previous step to document the monsoon season in various districts.

To that end for each district and state, I

  1. Calculated average and total daily rainfall over the five-year period
  2. Calculated average daily temperature over the five-year period
  3. Estimated the monsoon season's start and end dates
  4. Concisely presented my findings from (1), (2), and (3) by creating publication-quality tables and graphs