A climate station (left) and surface energy balance measurement system (right) setup on Commonwealth Glacier, Taylor Valley. Photo: Marte Hofsteenge
Validating drivers for meltwater generation models and regional climate variability
Researchers from the Antarctic Science Platform are developing Antarctic-wide and regional Ross Sea surface climate datasets. These datasets help to identify the local meteorological feedback processes that define air temperature variability near the surface. They are critical for modelling meltwater generation and understanding the drivers of regional climate variability.
One of Project 3’s goals is to understand how the availability and distribution of glacial meltwater will change with climate. This is because, on land, glacial melt is widely anticipated to be the critical link between climate change and terrestrial ecosystem response. The observations are being used to evaluate numerical weather/climate simulations and are assimilated with satellite-derived surface temperatures for wider spatial coverage across the Ross Sea region.
Annual mean air temperature trend for a) Antarctica Peninsula, b) Ross Sea Region, and c) East Antarctica from AntAir ICE 2003 to 2021. Dots mark a significant trend with a p-value <0.05. Dataset from Nielson et al, 2023. Figure source: Nielsen et al, 2024.
The research involves the development and testing of new methods. Researchers have tested a high resolution down-scaling approach from two different satellite datasets to gather climatic and hydrologic conditions where we don’t have field data (read more about deploying soil sensors), and used aerial surveying techniques (read more about thermal bird surveys). Researchers have also used Antarctic vegetation as a proxy for meltwater presence (read more about establishing sentinel sites for terrestrial Antarctic biology).
In situ
observations of climate variables, as well as supra-glacial processes and hydrological measurements, are critical to validate models of surface meltwater generation and hydrological routing.
Diurnal cycle of streamflow over the melt season of the six streams draining into Fryxell Basin for 2018/19 and 2021/22. Modelled streamflow is simulated using the WRF-Hydro modelling system and shown with a solid line. Observed streamflow with a dotted line. Credit: Tamara Pletzer
Highlights from the 2023-2024 Antarctic summer field season include:
- The team undertook maintenance and data collection at existing Automatic Weather Stations (AWS). Sites visited included Miers Valley, Miers Ridge, Commonwealth Glacier, Cape Christie and Haystack Mountain.
- They established new ridge-top Automated Weather Stations sites to complement valley-floor sites. The data from these new stations will be used to link regional weather patterns to those driven by local topography and boundary conditions. This is important because there’s growing evidence of localised climatic extremes (caused by seasonal warming events modulated by climatic processes at the regional scale), which can lead to hydrological extremes in areas of high biodiversity.
- They upgraded a new and long-term surface energy exchange station (which collects long term measurement of energy flux above glacier surface) at Commonwealth Glacier. This station provides data for understating variations of weather parameters and processes responsible for melt.
The AWS data is being added to international datasets, and the team are compiling data from stations maintained by national and international partners to progress the research. The data will be used to develop a better understanding of processes driving the variability of Antarctic mountain/coastal climates. The data also informs regional climate change projections and impacts on ecosystems of a warming world.
The University of Canterbury field team consisted of field leader, Dr Marwan Katurji, field technican Justin Harrison, and PhD students Marte Hofsteenge, Tamara Pletzer and Eva Nielsen.