The weather person on the evening news reports that the average daily rainfall for the last six months is 10 inches. A farmer is trying to determine how the rain might affect his crops. This report will be meaningless to the farmer unless he also knows the:
Ten inches a day? This question has an error.
The rainiest places on earth average a little more than one inch a year.
http://www.weather.com/news/science/nature/wettest-place-earth-20130529
This report will be meaningless to the farmer unless he also knows the variability or distribution of the rainfall. To assess how the rain might affect his crops, the farmer needs information about the frequency, intensity, and timing of the rainfall, not just the average daily rainfall.
By understanding the variability of the rainfall, the farmer can determine if the rainfall is evenly distributed across the months or if there are periods of heavy rain or drought. This information is crucial because crops have different water requirements at different stages of growth. For example, if the majority of the rainfall occurs in a short period of time, it may result in waterlogging and damage to the crops' root systems. On the other hand, if there is insufficient rainfall for extended periods, crops may suffer from drought stress and yield reduction.
Additionally, the timing of the rainfall is important. Depending on the crop, certain stages like planting, flowering, or fruiting, require specific moisture conditions. If rainfall consistently occurs during critical growth phases, it could benefit crop yields. Conversely, if rainfall is absent during these stages, it may lead to poor crop development.
To assess the impact of rainfall on crops accurately, the farmer should also consider other factors such as temperature, humidity, soil type, and crop varieties. Analyzing long-term weather patterns and historical data can provide more context and help the farmer make informed decisions on irrigation, fertilizer application, and other farming practices.