The release of a new continental-scale dataset, known as the Australian Phenology Product, is providing detailed information on the seasonal growth and development of Australia’s vegetation – indispensable for scientists and land managers nation-wide. From quantifying ecosystem resilience to climate change, bushfire fuel accumulation, native vegetation condition, and airborne allergens to informing agricultural management decisions and crop yields, the product’s list of real-world applications is almost endless.
Now available for download via TERN AusCover’s data portal, the product has been developed from the satellite derived MODIS Enhanced Vegetation Index (EVI) data and a suite of additional data collected and made available by TERN’s facilities. It quantifies vegetation life cycle dynamics, such as episodes of greening and browning, and analyses how these are influenced by seasonal and inter-annual variations in climate – known as land surface phenology (LSP).
Knowing how different parts of Australia’s vegetative land-cover are growing and developing with the change of seasons is vital information for environmental scientists, land managers and those in the agricultural and horticultural sectors.
|Now available for download via TERN AusCover’s data portal, the Australian Phenology Product has been developed from the satellite derived MODIS Enhanced Vegetation Index (EVI) (above) and a suite of additional data collected and made available by TERN’s facilities.|
Version one of the product, developed by Mark Broich during his time at the University of Technology, Sydney, is currently captures Australia-wide phenology at a 5.6km cell size resolution. Despite its coarseness, Mark says that such a resolution is of particular value to climate and ecosystem studies.
‘The product’s current release can be used to quantify vegetation condition and ecosystem response and resilience to climate variability and change, says Mark who is now a research fellow at the University of New South Wales.’
‘Scientists interested in the effects of ENSO cycles on Australia’s vegetation or land managers who would like to separate management effect from climate variability inside and outside of protected areas, will all benefit from the product,’
Fellow investigator Professor Alfredo Huete of the University of Technology, Sydney says that future plans to improve the product’s resolution to 1km or even 250m will expand its applications and enable it to be used by those in agricultural sectors.
‘Increasing the product’s resolution will give landholders and management agencies the capability to predict spatial and temporal biomass patterns for their crops and forage, and compare them with previous years’ growth and yields, as well as to provide insight into potential future yields,’ says Alfredo.
Such improvements in resolution would also enable users to monitor and quantify crop yields and make informed agricultural management decisions such as the timing of tasks including planting, fertilising, watering, and harvesting.
‘Quantifying inter-annual and inter-region differences in planting date or identifying double cropping systems are all possible,’ says Mark.
The product’s list of real-world uses isn’t limited to ecological and agricultural applications, says Alfredo. ‘Fire managers can assess bushfire fuel status and monitor the beginnings of dry-down periods,’ says Alfredo. ‘Public health officials can look at phenology events, such as grass flowering and pollen release, to monitor and map allergens.’
The product also provides valuable input and validation data to Australia’s land-surface models, which currently only have crude assumptions of the nation’s phenology, says Brad Evans, TERN’s Ecosystem Modelling and Scaling Infrastructure (eMAST) facility director and co-author of the product’s user guide.
‘Australia’s ecosystem modellers now have an observation based estimate of phenology which they can use in their models directly or as a validation of their models’ behaviour, says Brad. ‘This represents a significant improvement on previous data products available to the modelling community’
Such improvements in land-surface modelling will in-turn help predict future changes in Australia’s phenology including growing areas, seasons and growing cycles.
Especially designed to suit Australian conditions – highly variable and extreme climate seasonality, as well as inter-annual variability – the product fills an important information gap that global products failed to cover.
‘There is a global phenology product that works well for northern hemisphere temperature driven systems, but doesn’t work well over Australia’s rainfall-driven systems,’ says Mark.
‘For example, if you were to download the global phenology data product, there are lots of data gaps over Australia, simply because the algorithm isn’t developed for a dry climate with high rainfall variability like we have here.’
Mark and Alfredo also highlight the fact that their algorithms, on which the Australian-specific product is based, could be applied to other arid or semi-arid environments – ‘drylands’ – with similar conditions to Australia all around the world.
‘Given that drylands cover about 30% of the globe, it’s quite exciting to have such an algorithm!’ says Mark. ‘A huge number of complementary products could be developed that deliver similar positive outcomes [to the Australian product] worldwide.’
The Australian Phenology Product uses a range of infrastructure provided by TERN. Satellite data was accessed from AusCover infrastructure; data delivered by OzFlux, AusPlots, Australian Transect Network, and our Long Term Ecological Research Network were all used for developing and calibrating the product’s algorithms; and data from our network of ‘phenocams’ located at our monitoring SuperSites form an integral component of the product.
The product has also been developed to be consistent with TERN’s standards of data collection, handling, meta-data, licensing and methods – i.e. free download and usage licensing policies that provide easy access for everyone.
The Australian Phenology Product is now freely available via the AusCover data portal at: http://www.auscover.org.au/purl/phenology-modis-uts
Mark Broich is the lead author of two recently released peer-reviewed articles on the Australian Phenology Product, under the TERN AusCover flag, one of which is the dataset’s user guide:
- Click here to read the product’s official user guide in the journal Environmental Modelling & Software.
- Click here to read a Biogeosciences paper about how the Australian Phenology Product was used to quantify the change in vegetation phenology over eastern Australia when the Millennium Drought broke in 2010.
For more information on the Australian Phenology Product in general please contact Mark Broich or AusCover’s Sydney node based at the University of Technology Sydney.
Published in TERN newsletter March 2015