Copernicus AtmosHack – coordinating an innovation challenge at FMI

What an intense weekend behind! A massive amount of international collaboration and coordination culminated last weekend in Helsinki when we hosted the Copernicus AtmosHack at the FMI. The purpose was to find innovative use for satellite, in-situ, or modeled air quality data that will help people reduce exposure to air pollution. We had close to 80 people either hacking 24/7, mentoring, or taking care of practical arrangements. I was in charge of coordinating the event.

I learned that a hackathon is much more than coding for two full days. Ultrahack, one of the co-organisers, prefers the term innovation challenge, for good reasons. The most successful teams had versatile expertise beyond coding and data analysis skills. Their ability to bring the air quality data to life through functional applications or prototypes with creative graphics and business case ideas were astonishing.

The event was an overall success; I wrote more about the event itself to the FMI-SPACE pages. We had a great chance to gain visibility for FMI research in different media, including the national TV, where I was invited to talk about satellite data and the Copernicus program. Still, I think that the most valuable AtmosHack results are yet to be seen. These may emerge from an enhanced scientific collaboration with EUMETSAT and CAMS, or from exposing the clever, talented participants to environmental problems that they have the abilities to help solve in the future.


New paper: Ice crystals more reflecting in the near-infrared than previously modelled

Ray tracing is an efficient way of computing light scattering by particles much larger than the wavelength of light. The problem is that it really is an approximation. For my newly-published paper, I have coded a new version of the SIRIS ray-tracing code which treats one of the approximate approaches more exactly than before: the new ray tracer can consider inhomogeneous waves inside an absorbing particle and, therefore, leads to a more accurate solution for absorbing particles.

Ice crystals form the cirrus clouds in the sky. Ice crystal images from an aircraft-mounted Cloud Particle Imager show the variety of crystal shapes. 

We applied this code to solve scattering by ice crystals in the near infrared. Why ice crystals, and why near infrared? The thing is, ice crystals are very fascinating in the near infrared! Their complex refractive index varies greatly from 1 µm to 3 µm wavelengths: the crystals change from close to transparent to completely absorbing. These crystals are constantly present in the atmosphere and form thin ice clouds. That’s why we need to take them into account when we are looking at near-infrared radiation in the atmosphere – for example when measuring greenhouse gases using remote sensing.

What did we find? We found that ice crystals are systematically more reflecting in the near-infrared wavelengths than what has been modelled using traditional codes with approximations related to absorption. And we produced this new SIRIS code, which will soon become publicly available. This code can be used for computing scattering by non-spherical particles that are much larger than the wavelength of light. Thanks to colleagues at the University of Helsinki and University of Jyvaskyla for collaboration!

Link to the original paper, published in JQSRT.  

Link to FMI-SPACE story about this publication. 

The perfect chance for improved SciComm within the newly-established FMI-SPACE

The organisational makeover at FMI gave birth to a strong space-oriented research division called the “FMI Space and Earth Observation Centre”, or FMI-SPACE, where also my new group now belongs. This new division has great potential to improve the visibility of space and EO-related research and measurements carried out at the FMI, to all our stakeholders. Recognising the potential and the perfect chance for added visibility, the FMI-SPACE Communications team has now been formed. I’m leading this talented SciComm-oriented team of researchers who represent different FMI-SPACE research areas. The plan is that we collaborate with the FMI Communications but also produce more dynamic English-language content directed for professional use, e.g. for international collaborators and research funding agencies. We begin with creating our FMI-SPACE web pages which will have a major role in our SciComm later on.

New challenges for 2018: starting as the Head of Group at FMI

FMI is currently undergoing a major organisational change. As a small part of this process, I was selected as the head of the newly-formed Greenhouse Gases and Satellite Methods group. I am excited for this new possibility and look forward to learning a lot this year, especially from fields outside my current expertise, like from financial management of research and from ground-based measurements of GHG. The new group strategically brings together the people working with satellite GHG retrievals, development of mathematical methods and data-driven source-sink analysis with the people who run important GHG satellite validation measurements in Sodankylä (e.g., TCCON, AirCore). I have a feeling that there is a lot to gain in this newly-enhanced collaboration within FMI. This will require hard work from all of us but we are given a great chance to experiment, learn and renew the FMI GHG science and expertise together.

New paper: Satellite measures how the Earth is breathing

Our paper on “Does GOSAT capture the true seasonal cycle of carbon dioxide?” has been published at ACP (Atmospheric Chemistry and Physics)! In the paper, we study the average seasonal variability of satellite-retrieved carbon dioxide concentrations. This variability mostly comes from plant photosynthesis — in that sense, we poetically measure the breathing of our planet from space.

We compared 5 years of satellite measurements from the Greenhouse Gases Observing Satellite (GOSAT) to ground-based measurements at the TCCON sites, other retrieval algorithms, and inverse models that assimilate in situ measurements. This is the first time when the accuracy of satellite-retrieved CO2 seasonal cycle is thoroughly evaluated.

Main results:

  •  GOSAT seasonal cycle amplitude is generally accurate to within 1 ppm.
  • GOSAT maximum XCO2 is 2–3 weeks delayed from TCCON but minimum is accurately captured.
  • We found surprisingly that the differences between modelled seasonal cycles can be larger than GOSAT-to-model differences.

Academy of Finland post-doc

Earlier this year I was granted a three-year natural sciences post-doc position by the Academy of Finland (see press release). The topic of my successful research plan is “Clouds, aerosols and OCO-2: Quantifying the impact of small-particle light scattering on satellite-retrieved carbon dioxide”, and I will work on this topic at the Finnish Meteorological Institute, collaborating with the Nasa OCO-2 Science Implementation Team and Colorado State University.

Post to CSU SoGES blog

A blog post of mine, entitled The Hunt for the Mysterious Carbon Sink, just got published at the School of Global Environmental Sustainability’s (SoGES) blog. I wanted to write about the land CO2 sink, and why it is so crucial in terms of the current and future climate change. The topic is strongly related to the motivation of my current research in the OCO-2 project, although not directly about my own studies. I wrote this blog text as a part of my Sustainability Leadership Fellow 2014-2015 program at Colorado State University.