- Geodesist Xiaoxiang Zhu wins 2018 PRACE Ada Lovelace Award for HPC
- Remote earth observation can assess global population density and provide clues to climate change
- Zhu says award brings responsibility of boosting other women in scientific fields
What can you discover about the earth from space?
A lot, says Xiaoxiang Zhu, Head of Signal Processing in Earth Observation at the Technical University of Munich and head of department of EO Data Science at the German Aerospace Center, who uses satellite remote sensing to create data-rich topographical maps of our entire planet.
Zhu is the 2018 winner of the PRACE Ada Lovelace Award for HPC. Initiated in 2016, the award recognizes an early-career female scientist working in Europe who has had an outstanding impact on HPC research and who provides a role model for other women beginning careers in HPC.
Combining data from Copernicus, the European Union’s Earth Observation Programme, and from the German Aerospace Center, Zhu and her team derive maps on a global scale that will observe changes to cities over time, create 3D models of buildings and their functions, and also provide the first-ever transparent estimation of population density.
“In Europe, we have a very well-mapped environment. But in developing countries, particularly in areas with informal settlements and slums, the authorities don’t have access to basic information,” Zhu says.
“Lack of data means it’s difficult to scale fundamental infrastructure like health care, clean water, and education according to actual population density,” she adds. “We are about to close this gap between nations and take the first step to provide this kind of information.”
Global processing of petabytes of geospatial data requires big computing power. Working at a resolution of approximately ten meters means high-performance computing is absolutely essential. Since 2012, Zhu has used over 46 million core hours on the SuperMUC computer at the Leibniz Supercomputing Centre.
“From the beginning, the data I/O and data storage alone required support from HPCs. When we get the data ready to process, we need supercomputers to be able to get results on a global or even city scale,” Zhu says. “And then, in order to convey our results to the public, the visualization of the data will again need HPC.”
But, Zhu emphasizes, computation is only one aspect of her research. In addition to difficulties with storing such vast amounts of data, processing the satellite imagery presents its own challenges. Images must be modified to remove clouds and scientists must figure out how to fuse together images from different sources.
“If we could have the computational details simplified,” Zhu says, “then our focus could be only on trying to improve the algorithm to reach the best accuracy. What I’m trying to do is better understand global organization and problems like climate change.”
Combining passions for success
About her decision to pursue a career in science, Zhu says, “When I was very young, I saw a picture of Earth taken from space and I thought ‘Wow, that’s really fantastic!’”
But she’s also interested in mathematic models, and likes to work with people from different fields. “In earth observation, a lot of mathematics are involved, and we deal with data taken from space,” she says. “My team is very interdisciplinary—physicists, mathematicians, computer scientists, urban geographic scientists—we all work together. This is just what I wanted.”
Zhu believes that winning the award will help advance her connections in the HPC field and further her own research. But she says that accepting the award also brings a responsibility to assist other women working in science and HPC.
For Zhu, this means trying to recruit more female team members, which she admits is sometimes difficult because there are fewer female candidates. She is also involved in groups that work to promote the participation of more women in all scientific fields.
“Winning this award means that I should be a disseminator, who speaks for more women in HPC,” she says. “I’m very delighted to do this.”