When The Rains Stop

• Did you know, that researchers have found by checking lake beds and tree rings, that droughts appear in regular cycles.
• Did you know that two of the main traceable cycles happen to  hit at the same time, (now)?
• Did you know that in the traceable history of droughts, that the seven year dust bowl drought of the thirty's was considered a "short" drought?
• Did you know that droughts usually start in the east and move to the west.
• Did you know the present drought started in the east in 1999?

Why the West Is Burning, click here A five-year drought has parched soils, lowered reservoirs and weakened forests. And if the past is any guide, the dry spell could go on for decades, By J. MADELEINE NASH/SAGE

Links To Current US Drought With Maps Droughts More Severe Than 1930s Expected Understanding Droughts (May article) Nov Article DROUGHT IS HELL Precipitation Last Month Map Weekly Precipitation Map Drought Definition Click Here

DROUGHTS ARE NOT AN EXACT SCIENCE

Unlike weather forecasting, Climatologists deal with years.  One 6 inch rainstorm out of nowhere could make this predictions for this year look foolish in your area.  Therefore you will have drought forecasts tempered with, "indications are"  "likely"  and   "overdue". 

DEFINING WHAT IS A  DROUGHT?

There are four different ways that drought can be defined:
Meteorological - a measure of departure of precipitation from normal.  Due to climatic differences what is considered a drought in one location may not be a drought in another location.
Agricultural - refers to a situation when the amount of moisture in the soil no longer meets the needs of a particular crop.
Hydrological -  occurs when surface and subsurface water supplies are below normal.
Socioeconomic - refers to the situation that occurs when physical water shortage begins to affect people.

AGRICULTURAL DEFINITION OF DROUGHT 

Drought is a protracted period of deficient precipitation resulting in extensive damage to crops, resulting in loss of yield.

Lack of rainfall for an extended period of time can bring farmers and major metropolitan areas to their knees.  It does not take very long; a few rain-free weeks spreads panic and shrivels crops.  We are told to stop washing our cars, cease watering the grass and take other weather conservation steps.  Continued sunshine without sufficient rain can turn a rain forest into a desert; so maybe sunny weather is not always the best weather.
The Dust Bowl days of the 1930's affected 50,000,000 acres of land, rendering the farmers helpless.  In the 1950's the Great Plains suffered a severe water shortage when seven years went by with rainfall well below normal.  Crop yields failed, the water supply fell.

DEFICIENT TOPSOIL MOISTURE

A good definition of agricultural drought should be able to account for the variable susceptibility of crops during different stages of crop development, from emergence to maturity.  deficient topsoil moisture at planting may  hinder germination, leading to low plant populations per hectare and a reduction of final yield.  However, if topsoil moisture is sufficient for early growth requirements, deficiencies in subsoil moisture at this early stage may not affect final yield if subsoil moisture is replenished as the growing season progresses or if rainfall meets plant water needs.  

CONCEPT OF DROUGHT

Drought is an insidious hazard of nature.  Although it has scores of definitions, it originates from a deficiency of precipitation over an extended period of time, usually a season or more.  This deficiency results in a water shortage for some activity, group, or environmental sector.  Drought should be considered relative to some long-term average condition of balance between precipitation and evapotranspiration (i.e., evaporation + transpiration) in a particular area, a condition often perceived as "normal".  It is also related to the timing (i.e., principal season of occurrence, delays in the start of the rainy season, occurrence of rains in relation to principal crop growth stages) and the effectiveness of the rains (i.e., rainfall intensity, number of rainfall events).  Other climatic factors such as thigh temperature, high wind, and low relative humidity are often associated with it in many regions of the world and can significantly aggravate its severity.  Drought should not be viewed as merely a physical phenomenon or natural event.  Its impacts on society result from the interplay between a natural event (less precipitation than expected resulting from natural climatic variability) and the demand people place on water supply.  Human beings often exacerbate the impact of drought.  Recent droughts in both developing and developed countries and the resulting economic and environmental impacts and personal hardships have underscored the vulnerability of all societies to this "natural" hazard.

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