Earth-observer in chief

By Ben Iannotta|April 2017

JOSEF ASCHBACHER

Under the Trump administration, the U.S. is expected to rethink how and why it conducts Earth science research, especially anything related to climate change. By contrast, the way ahead for Europe has been firmly set since the late 1990s. The European Space Agency and European Union are in the midst of launching a multibillion-dollar series of satellites, called Sentinels, that for decades to come will measure land change, ocean height, carbon dioxide and a host of other factors. The data will guide European officials on issues from natural-disaster response to climate policy. I spoke by phone with Austrian scientist Josef Aschbacher, director of the European Space Agency’s Earth observing programs, to discuss the arrival of the new administration in Washington and what it might mean for Earth observing.

In his words

Challenge of Copernicus

What makes it so ambitious is that it is a long-term operational program. We have now already funded infrastructure, meaning satellites, to date through 2030 and of course there’s a plan to have satellites afterward. It’s a continuous, longtime mission and of the same type of sensors with improvements along the way. So a little bit of what we are already doing with meteorology already, successfully, where we have one satellite following the other in a longtime series of the same measurements, in this case applied for agriculture, forestry, marine applications, atmospheric measurements, climate observations and so on.

Politicians, technologists on same page

We need a long-term observation capability which doesn’t exist, neither in NASA nor in Europe. So this was one of the drivers to establish a more operational system as compared to a scientific mission, where very specific questions are being addressed one by one, and mission by mission. What European politicians, technical people, together, considered [as] important was a long-term observation capacity.

Why Europe doesn’t have a CO₂ satellite yet

Measuring CO₂ from space is rather complex and not so easy, not so straightforward. In order to have a meaningful CO₂ measurement, we need to well understand the fluxes in the atmosphere and these changes of carbon between the various elements — the ocean surfaces, the land surfaces, the atmosphere. This obviously requires a high resolution of sensors. High means less than 10 square kilometers. And frequent observations, at least once a day, if not more often. And an instrument that can do this, to really meaningfully retrieve CO₂ , [has] not been developed. Technology is still a challenge and this is something that we are starting now.

CO₂ highest priority

CO₂ is the number one priority. We are starting now studies to see exactly what this could mean in terms of satellites, measurements, user requirements, which missions will be required. This is work which is ongoing now. There is an international task force which is looking into this. We actually have some U.S. and Japanese members on this task force, as well as Europeans, to really see what such a CO₂ architecture could look like.

A step beyond NASA’s Orbiting Carbon Observatory-2

What we have today is NASA’s OCO, then the Japanese GOSAT, also China has just in December launched a mission called TanSat, which are measuring carbon dioxide. So, what we want to dream up is something complementary and, I would say, the next generation, or next step in this evolution. Something that has a wide swath width and a high enough resolution to really understand better these processes and the fluxes of carbon dioxide. Of course we will work with, quite closely with, our U.S. colleagues but also other colleagues from other countries.

Cooperation with U.S. at risk

I would strongly wish and hope that the U.S. will be a strong partner in this activity, not only in the CO₂ monitoring part, but also in some of the other activities in Earth science. We already have an excellent cooperation, and in many cases working without the U.S. would not be feasible. U.S. scientists and the U.S. science community simply have a very, very strong and very good knowledge of many aspects of the Earth system.
I think at the end of the day, it will be at the benefit of America to participate in these activities because it goes way beyond climate change. Sometimes people say “climate research” but of course this instrument measures many parameters which are very beneficial to the society and country, the U.S. in this case, but also other countries. So therefore, I think this is not a black and white position, or a black and white view. It really has to be seen in a much wider context.

Earth science means more than studying climate

There are many other good reasons for observing the Earth system. As I said, sometimes I hear the notion that Earth science at NASA is limited to climate change. No. I think the Earth scientists at NASA are doing a thousand things and they are for many applications: agriculture, to forestry, resource management, environmental monitoring, or to make sure people, in this case in the U.S., but also around the globe, understand how the Earth system functions and therefore one could be there in case of disasters, in case of climate change to address these issues.

Possible transfer of NASA Earth sciences to NOAA

I can certainly say from the European example, or European perspective, once you have an expertise accumulated over decades in Earth science, it is not something that can just be transplanted from one place to the other. Expertise is bound to people and people represent the history and also do all the capital investment which there is. So I think this is something that whoever makes these wise decisions would be very likely to consider.