Probe use while upside down CSIRO LAND AND WATER / WATER FOR A HEALTHY COUNTRY David McJannet & Aaron Hawdon CosmOz Australian cosmic-ray soil moisture observing network

CosmOz - Australian cosmic-ray soil moisture observing network CosmOz - funded in 2010 through internal CSIRO budget 11 probes were purchased– last one installed June 2011 Developed collaborative network with Uni Tas, Uni NSW, Monash Uni, Charles Darwin Uni Co-located with other measurements e.g. flux towers, water balance, CalVal, crop growth Current funding: 0.75 full time person Cosmic-ray soil moisture measurements | David McJannet 2 |

CosmOz monitoring locations Cosmic-ray soil moisture measurements | David McJannet 3 |

Bit of geography... 80% live within 50 km (30 miles) of coast Cosmic-ray soil moisture measurements | David McJannet 4 |

CosmOz setup Cosmic-ray soil moisture measurements | David McJannet 5 | Satellite link Rain gauge Solar panel Data logger Pressure sensor (temperature & humidity soon) Small concrete pad Neutron tube (moderated)

Cosmic-ray soil moisture measurements | David McJannet 6 |

The CosmOz network: Data delivery Cosmic-ray soil moisture measurements | David McJannet 7 |

Where are we up to? All probes installed Longest record – 2 yrs Shortest record – 1.25 yrs Very reliable - one cable failure and one probe replaced Calibrations – Aiming for a wet and a dry calibration per site (at least) 4 sites have 2+ calibrations 6 sites have dry calibrations Lattice water sampling currently underway Data processing approaches defined and being implemented Cosmic-ray soil moisture measurements | David McJannet 8 |

Observations and discussion points 9 | Cosmic-ray soil moisture measurements | David McJannet Corrections Pressure Vapour Dosage Calibrations Surface runoff Probe corrections and data smoothing

Weany Creek 2011 – Vapour Correction Corrections – Vapour pressure Standard COSMOS correction applied Where possible we use local site data Plan to add Hydroinnova T & RH to each site Cosmic-ray soil moisture measurements | David McJannet 10 | 10%

Corrections – Atmospheric Pressure Inspired by Marek’s Hurricane Sandy slide - Cyclone Yasi Category 5 cyclone km/h (180 m/h) Cosmic-ray soil moisture measurements | David McJannet 11 | Weany Creek Probe

Dealing with the aftermath... Cosmic-ray soil moisture measurements | David McJannet 12 |

Corrections – Atmospheric Pressure Corrections range by 20% Cosmic-ray soil moisture measurements | David McJannet 13 | Weany Creek Probe

Corrections – Cosmic-ray dose (discussion) CosmOz cut-off rigidity varies from 2 – 13 Originally extracted site specific dosage (kspc22.unibe.ch) but stopped in early 2012 Moved to data from NMDB.eu using Swiss station but found some issues after discussions with Marek... Cosmic-ray soil moisture measurements | David McJannet 14 |

Cosmic-ray soil moisture measurements | David McJannet 15 | Corrections – Cosmic-ray dose Solar Flare

It does make some difference – which is more correct? For now CosmOz sticking with nearest Rigidity NMDB.eu site Keep in mind this could be important when the world ends on 21 st Dec! Corrections – Cosmic-ray dose Cosmic-ray soil moisture measurements | David McJannet 16 | Solar Flare Up to 10% difference

Calibration of CosmOz probes 24 sampling points – 8 points in each of 3 concentric rings 3 depths at each point = 72 samples (0-5, 10-15, 25-30cm) Collect wet and dry soil calibration points Standard calibration function tuned to measurements using one free parameter Cosmic-ray soil moisture measurements | David McJannet 17 |

Calibration – Weany Creek Cosmic-ray soil moisture measurements | David McJannet 18 |

Cosmic-ray probe and lattice water Lattice water samples being prepared for ACTLABS For now using relationship between lattice water and clay content for Australian soils Cosmic-ray soil moisture measurements | David McJannet 19 |

Calibration – Weany Creek Cosmic-ray soil moisture measurements | David McJannet 20 | Add in lattice water estimate

Calibration – Tullochgorum Cosmic-ray soil moisture measurements | David McJannet 21 | Add in lattice water estimate

Calibration – Robson Creek Cosmic-ray soil moisture measurements | David McJannet 22 | Add in lattice water ??? Is this a soil carbon effect?

Calibration - Gnangara Soil almost pure silica sand Collected one wet calibration point (assume no lattice water) Applied calibration to whole time-series Cosmic-ray soil moisture measurements | David McJannet 23 |

Calibration - Gnangara Standard curve fit not applicable (<2%!) Empirical fit and more data points required Cosmic-ray soil moisture measurements | David McJannet 24 | -ve!

Weany Creek -case study Cosmic-ray soil moisture measurements | David McJannet 25 | Weany Creek

Weany Cr - measurement depth and fluxes Cosmic-ray soil moisture measurements | David McJannet 26 | Water flux (mm) Infiltration Drainage and evaporation

Discussion points – Probe corrections & Filtering At least 4 four probe types – is there a need for comparison of ‘standardised count’? i.e. San Pedro Cosmic-ray soil moisture measurements | David McJannet 27 |

CosmOz future directions 28 | Cosmic-ray soil moisture measurements | David McJannet

Future – South East Esk Sensor Web Smart irrigation project Balancing farmer, hydro- power and environment needs Measurements coupled with flow/rain prediction (1km grid, 6 hr) Near real-time decision making 3 cosmic-ray probes Cosmic-ray soil moisture measurements | David McJannet 29 |

Future – Potential adopters Apart from CSIRO and uni researchers the Bureau of Meteorology is a potential adopter Bureau of Meteorology has interests in weather prediction and water balance accounting Recent seminars given to demonstrate potential uses of cosmic-ray probes Used combination of CosmOz and COSMOS progress Lots of interest in applications from various groups...no commitments as yet...watch this space! Hopefully you will hear more about CosmOz at future meetings Cosmic-ray soil moisture measurements | David McJannet 30 |

CSIRO LAND AND WATER / WATER FOR A HEALTHY COUNTRY David McJannet