25 years ago, in 1992, 1700 independent scientists already told us in their “World Scientists – Warning to Humanity – 1st Notice”. And yet, it seems that was not sufficient. This month, a second notice was submitted, this time by about 15,000 worldwide scientists. And the message is still quite clear: “the world is going toward catastrophic biodiversity loss and untold amounts of human misery” and we have little time to act before avoiding this.
This may sound like an unrealistic, even irrational alarmist message. But it is worth reminding that, since its beginning, science work (and scientists) is beforehand based on observations, facts, interpretations with evaluation of uncertainties, implementing models that are then continuously and thoroughly evaluated by confronting with observations.
This article is relatively short and very simple to read. No need to be an expert, every citizen can easily understand all the messages. I think this is the duty to each of us to take some minutes for reviewing it, and then thinking about our actions. Especially, the causes are nowadays well identified: rapid population growth, deforestation, agricultural production, and rising greenhouse gases from burning fossil fuels that has triggered and driven our climate change.
For this last one, in spite of continuous denial and unjustified claims (especially in the USA), the odds from IPCC and COP23 are pretty clear: CO2 – Carbon dioxide and CH4 – Methane amount in the atmosphere are historically unique, and the emissions keep increasing. Some of these increases are also even observable from space.
A positive sign: stratospheric O3 – Ozone hole over Antarctic is recovering. If our actions have allowed to create and then solved this problem, then we can still do something, at every level, about the greenhouse gases.
Several journals and websites forwarded this article. But I have the feeling yet it could reach more and more people and lead to further discussions and actions in our societies. Hope this is not too late…
Ripple et al., 2017: Full articles World Scientists’ Warning to Humanity, 1st and 2nd notices here. You can also endorse the 2017 article here
European Space Agency (ESA): CO2 – Carbon dioxide and CH4 – Methane on the rise here
What happened on Monday 16th October 2017? From diverse countries (France, United Kingdom, the Netherlands, Finland), people reported to have observed a “red Sun”. This is a direct result of natural events, although issued from different sources and locations, which combined together over the whole Europe.
During a couple of days, between 16th and 18th October 2017, northern Portugal and Spain were victims of violent wildfires ravaging parts of their territory. These fires released large amounts of fine black particles, also named aerosols, that can absorb the Sun light.
The Copernicus Atmosphere Monitoring Service (CAMS) forecasts of aerosol optical depth (AOD) show high values extending from the Iberian peninsula to the British Isles.
In addition to these fires, a tropical storm, named Ophelia, appeared 1300 km south-west of the Azores islands and some 2000 km off the African coast. Originally classified as a tropical storm, it was upgraded to a hurricane. The storm moved north-easterly, towards Spain and Britain, collecting sand from the Sahara desert. The related dust particles were then mixed with the black carbon from Portugal fires. Their scattering properties with the solar light led to this red Sun observed by many Europeans, instead of its natural yellow colour in clear sky or white/milky in presence of thin cloud.
The dust particles can be observed through the visible colour composite image from the MODIS instrument, on-board Aqua, on 16.10.2017: some yellow colours are mixed with some thin clouds.
It remains, overall, challenging for satellite measurements acquired in the visible spectrum to easily distinguish dust particles from transparent clouds or cirrus.
GOME-2 and OMI satellite sensors also reveal through the AAI index, with high values in red, the presence of black absorbing particles (i.e. smoke from biomass fires in Portugal) in large quantity. These particles were released in the North of Portugal before being transported to the North (UK) and then East (the Netherlands, Finland and Russia).
Although the aerosol particles were the visible part of the pollutant transport, IASI sensor revealed the additional presence of CO – Carbon monoxide, a toxic gas issued from incomplete biomass combustion by the fires. CO is a gas pollutant that cannot be visible in the eyes. It can only be measured in the shortwave or thermal infrared spectrum such as the IASI measurement.
All these worldwide satellite pictures very well illustrate that, although emissions can be national, mix of pollutants and their transport are not contained within the limits of borders. This shows how much pollution and their scientific and societal challenges are an international concern!
CAMS, Saharan dust and smoke over France and UK here
GOME-2 AAI index by KNMI, EUMETSAT AC SAF & TEMIS here
Why are we (I and my colleagues) that excited this week? Why is TROPOMI so much important for the new coming era in air quality & climate satellite era?
Throughout the week, we will post more information on our GRS TU Delft website and also be using the #GRS_TROPOMI on social media (Twitter and Instagram) as we explain more about the mission, its goals, and how it all works in relation to the goals and work being done in our department. The week will culminate with the Sentinel-5P launch event taking place at the Space Expo in Noordwijk.
Despite its quite advance age for a satellite mission (13 years old!), OMI is still delivering remarkable measurements about our atmospheric composition and air quality. So many talks and discussions on the aerosol global record over cloud-free scenes and above clouds, decade global volcanic SO2 – Sulfur dioxide missions, the use of OMI data by air quality model simulations to inform air quality policy, the case studies on emissions monitoring and to support authorities and clean-tech industry, the new generation of the Quality Assurance For Essential Climate Variables (QA4ECV), the evolution in the ozone trends and related mechanisms, and of course the future with the forthcoming TROPOMI (Sentinel-5 Precursor) mission, TEMPO (NASA Geostationary) and TROPOLITE.
In spite of being glad of having been part of this adventure, I cannot stop myself thinking this may have been my very last OMI conference, before finishing my current research project and starting new professional & personal adventures (still in satellite & atmospheric community of course!). But this last point will be specifically mentioned later in future weeks. Stay tuned!
Finally, that’s official! TROPOMI, on-board Sentinel-5 Precursor, the 1st European operational satellite mission devoted to air quality, ozone & climate monitoring, should be launched within the next weeks. And this looks very impressive!
The 20th OMI Science Team Meeting will be held at NASA Goddard in Greenbelt MD, USA from Tuesday September 12 through Thursday September 14, 2017. With nearly 14 years of data and the impending launch of TROPOMI on board-Sentinel-5 Precursor, there is much to discuss within the OMI (& TROPOMI) team and user community regarding the current state of OMI, trends and longer-terms records, comparisons with (satellite) data sets, and the validation of OMI data. This meeting will highlight recent OMI results as well as address research plans and program goals for the coming year.
And it is still very interesting to observe not only the temporal variability of temperature, CO2 – Carbon dioxide concentrations and relative humidity but also the apparent nice correlations between them! Especially, CO2 in our office and temperature seem to follow similar diurnal variation. Of course, these variables, at a such local scale, are also strongly dependent on external parameters such as wind transport, the number of people present in the room, whether the windows are open etc…
CO2 – Carbon dioxide, an important greenhouse gas and its impacts on our changing climate here