Drought is a prolonged, abnormally dry period when the amount of available water is insufficient to meet normal use. There is no universal definition of drought. Meteorologists monitor the extent and severity of drought in terms of rainfall deficiencies. Agriculturalists rate the impact on primary industries, hydrologists compare ground water levels, and sociologists define it by social expectations and perceptions.
It is generally difficult to compare one drought to another, since each drought differs in seasonality, location, size and duration. This is, in part, due to the different climate drivers from the Pacific, Indian, and Southern Oceans that can influence variations in rainfall (such as the El Niño-Southern Oscillation and Indian Ocean Dipole).
With a variable climate, drought has been a constant and inevitable feature of the NSW landscape. Dry conditions should be considered in the same light as other business risks.
Over time, NSW has moved away from treating droughts as natural disasters that require emergency responses. Planning for dry conditions over the long-term is the most effective way to prepare for drought and other downturns.
NSW Department of Primary Industries, working with the independent Regional Assistance Advisory Committee (RAAC), developed the Enhanced Drought Information System (EDIS) project and the Combined Drought Indicator (CDI) to track all phases of drought onset and recovery.
The CDI combines meteorological, hydrological and agronomic definitions of drought using indexes for rainfall (RI), soil water (SWI) and plant growth (PGI), and a fourth index, drought direction (DDI), to account for direction of change. The CDI uses the first three indices to account for a combination of variables that affect drought conditions beyond rainfall deficiencies, including factors such as high temperatures (evaporation), runoff, soil infiltration, and rainfall intensity.
Used together, these indexes can indicate the five phases of drought: Non Drought, Recovering, Drought Affected, Drought, Intense Drought.
NSW DPI presents the CDI drought indicator drought maps in conjunction with the Bureau of Meteorology, CSIRO Oceans and Atmosphere, Geoscience Australia, International Centre for Applied Climate Sciences, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES), NSW Local Land Service, NSW Rural Financial Counsellors and the NSW DPI Rural Resilience Network.
As drought is an inevitable feature in our landscape, it is considered in the same light as other risks to farm businesses. A whole-of-government response to drought has been introduced to ensure coordination of service delivery to the broader rural community.
The NSW Drought Strategy encourages primary producers to plan ahead in normal conditions to prepare and build in flexibility to deal with adverse conditions.The NSW Government works with industry and stakeholders to enhance farmers' drought preparedness through a suite of assistance measures.
NSW Government responses to drought complement Commonwealth assistance measures, and are aligned with the Intergovernmental Agreement on Drought Program Reform.
The NSW Drought Interagency Working Group ensures a whole-of-government approach is taken to drought policy and the implementation of the NSW Drought Strategy.
The working group draws on a range of regional networks to:
The working group meets every two months or as required, and comprises representatives from:
The working group is chaired by the NSW Department of Primary Industries.
During the second half of the 19th century increased population and droughts led to increasing the intensity of farming and attempts to 'drought proof' agriculture through the expansion of irrigation.
While there are localised drought events in parts of the state or country, the most recent major drought events were:
In addition to these multi-year droughts, there have been a number of short, intense droughts (e.g., 1914-1915, 1965-1967, 1982-1983).
The current drought began in NSW in mid - 2017 and it is equivalent to a major drought event on the long term historical record (100 years).