The Stochastic Climate Library (SCL) is a library of stochastic models for generating climate data.

This version of SCL (Version 2.2) has stochastic models for generating:

Single site rainfall at the following timescales:

• Sub-daily;
• Daily;
• Monthly; and
• Annual.

Single site climate (Rainfall, Evaporation, Maximum temperature) at the following timescales:

• Daily;
• Monthly; and
• Annual.

Multi-site rainfall at the following timescale:

• Daily.

Other stochastic models may be added to future versions of SCL after model development and testing.

SCL is designed for hydrologists, environmental scientists, modellers, consultants and researchers to facilitate the generation of stochastic climate data.

SCL is easy to use and is based on relatively robust stochastic climate data generation models.

Stochastic climate data can be used as inputs into hydrological and ecological models to quantify uncertainty in environmental systems associated with climate variability.

What is stochastic climate data?
In short, stochastic climate data are random numbers that are modified so that they have the same characteristics (in terms of mean, variance, skew, long-term persistency, etc...) as the historical data from which they are based. Each stochastic replicate (sequence) is different and has different characteristics compared to the historical data, but the average of each characteristic from all stochastic replicates is the same as the historical data.

What is the use of stochastic climate data?
Using historical climate data as inputs into hydrological models provides results that are based on only one realisation of the past climate. Stochastic climate data provide alternative realisations that are equally likely to occur, and can therefore be used as inputs into hydrological and ecological models to quantify uncertainty in environmental systems associated with climate variability. Stochastic climate data are traditionally used in storage yield analysis to estimate reservoir size for a given demand and reliability, or to estimate system reliability (number and levels of water restrictions) for a given storage size and demand characteristics. Stochastic climate data can also be used as inputs into water resources models (like REALM and IQQM) to estimate system reliability (e.g., water allocation amounts for competing users) for alternative allocation rules and management practice.

SCL is a library of stochastic models for generating climate data. This version of SCL has eight models for generating rainfall and climate data (see above). The models in SCL have been tested using data from many sites across Australia.

• Allows easy use of stochastic climate data generation models
• Runs quickly
• Supports various time series input data formats
• Displays input time series and stochastically generated data graphically
• Allows easy retrieval of the stochastically generated climate data
• Provides a graphical display of the empirical distribution of stochastically generated data and historical data. These plots allow quick easy comparison of the distributional shape at various aggregation levels. For the daily models annual maxima curves are also produced - providing Depth-Frequency-Duration curve validation.
• Displays the mean and percentiles of various statistics of the generated data and the corresponding values in the historical data (as tabulated values, scatter plots and whisker plots) - values can also be written to a file
• Provides statistical summary and assessment of the quality of the stochastically generated data.