2017 is about finishing, 2018 is going to take over. Here is a personal retrospective view on 2017 with a subjective selection of remarkable satellite images.
Wildfires across the globe
Massive wildfires spread across parts of the world such as Chile; Western Canada and the United States; Portugal and Spain; France and even Greenland in 2017. The most recent once, California’s Thomas Fire, was even the largest wildfire of the year in the state. MODIS AquaAqua, Sentinel-2 and many other space-borne instruments reveal these episodes and their intensity. Due to the on-going changes in our climate, it is unfortunately expected that such fires will occur again in 2018, perhaps even stronger.
Natural-color images from MODIS-Aqua sensor, over east Canada within the period of 2017.07.31-2017.08.08. Red points indicate actively burning areas identified from MODIS, on-board Terra and Aqua platforms. Smokes stretch very far away from these points (Source: https://worldview.earthdata.nasa.gov).
Red Sun, dust and smoke in Europe
In October 2017, a unique combination of 2 independent events – fires in Portugal & Spain, and a tropical storm – brought dust and smoke all over Europe leading then an unusual red Sun observed in France, UK, Finland and the Netherlands. These events were observed notably by OMI, GOME-2 and MODIS Aqua. More information in No borders for particles! – Red Sun, Saharan dust and smoke over whole Europe
MODIS-Aqua visible image on 17.10.2017 (right) acquired in early afternoon: dust particles in yellow over France, united Kingdom and the Netherlands (Source: https://worldview.earthdata.nasa.gov)
California wildfire lights in, Puerto Rico lights out
Satellite images of Earth “night lights” have been a curiosity for the public and a tool of fundamental research for at least 25 years. New global maps have been released by NASA’s Goddard Space Flight Center using the NASA-NOAA Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite. Some of them depict in an impressive way some dramatic episodes of this year: Hurricane Maria struck Puerto Rico, a commonwealth of the United States, leaving the island devastated and all but destroying its power grid; the fast-moving fire that swept into Ventura, California, on December 5, 2017. looking as bright as the urban Los Angeles area.
SUOMI-NPP images o night light in Puerto Rico on September 27-28 2017. One image in each pair shows a typical night before Maria made landfall, based upon cloud-free and low moonlight conditions; the second image is a composite that shows light detected by VIIRS on the nights of September 27 and 28, 2017. By compositing two nights, the image has fewer clouds blocking the view. (Note: some clouds still blocked light emissions during the two nights, especially across southeastern and western Puerto Rico.) The images above show widespread outages around San Juan, including key hospital and transportation infrastructure. Credit NASA (Source: https://earthobservatory.nasa.gov/IOTD/view.php?id=91044).
Of course, how not to finish this series without mentioning Sentinel-5 P and its instrument TROPOMI? Many persons waited for it for more than 10 years. I personally heard about it the first time some 5-6 years ago, and then waited for its launch during the last 4 years while working on my research with its predecessor OMI. And finally, just a few months before the end of my current job, Sentinel-5 P was launched, a very happy Friday 13th (October)!
With its unique high spatial resolution (7 x 3.5 km2) and top design sensor, this is the very first European operational mission dedicated to atmospheric composition within the Copernicus programme. The instrument is still under calibration until April 2018, being prepared for the developed services, and many works have to be done to derive accurate estimations of toxic gases and particles in the atmosphere. But the very 1st revealed maps of NO2 – Nitrogen dioxide, SO2 – Sulphur dioxide, O3 – Ozone, CO – Carbon monoxide are already outstanding. What is mostly remarkable are the very fine scale structures of all the pollution plumes already visible.
No doubt that the next months and years will be promising for this instrument. Air pollutants will be seen in much more detail than what has been accomplished before. And, while these first results demonstrate the sophistication of the satellite’s instrument, they certainly bring the issue of air pollution sharply into focus. Even though I am going to work on another project in 2018, I will keep a close eye on the next results from TROPOMIS5P.
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
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
“Our house is burning and we are looking somewhere else. Nature mutilated, overexploited is not able to recover and we refuse to admit it. From North to South, it suffers from ill-development, and we are indifferent. Earth and humanity are in great peril and we are accountable” (from my own English translation).
Those were the words pronounced by our former French president in 2002 in Johannesburg (South-Africa) in 2002 during the Earth summit. The real French words pronounced were the following: “Notre maison brûle et nous regardons ailleurs. La nature, mutilée, surexploitée, ne parvient plus à se reconstituer et nous refusons de l’admettre. L’humanité souffre. Elle souffre de mal-développement, au nord comme au sud, et nous sommes indifférents. La terre et l’humanité sont en péril et nous en sommes tous responsables.”
At that time, large wildfires were ravaging Australia and societies were debating on the responsibility of climate change. 15 years later, 2017, these words are somehow ringing a bell to me. When looking at all the twitter posts during the last 2 months, we quickly get the feeling that Earth is on fire.
A series of blazes has burned in the vicinity of Kangerlussuaq, a small town that serves as a basecamp for researchers in the summer to access Greenland’s ice sheet and western glaciers. The largest fire has burned roughly 3,000 acres and sent smoke spiralling a mile into the sky, prompting hunting and hiking closures in the area, according to local news reports. There’s no denying that it’s weird to be talking about wildfires in Greenland because ice covers the majority of the island. Forests are basically non-existent and this fire appears to be burning through grasses, willows and other low-slung vegetation on the tundra that makes up the majority of the land not covered by ice.
Most of Greenland is covered by ice up to 3 kilometres thick but there is some tundra around the coastline. The wildfire is burning on tundra in the west of Greenland, near the small town of Sisimiut. The larger fire could be a result of melting permafrost, McCarty told Wildfire Today. As the once-frozen ground melts, the upper layers can dry out and become flammable if they are full of organic matter. Stef Lhermitte, a remote sensing expert at the Geoscience & Remote Sensing department (GRS) of Delft University of Technology (TU Delft) in the Netherlands, said there is evidence of fires burning in Greenland over the past 17 years of MODIS satellite records kept by NASA.
“It certainly is the biggest one in the satellite record,” says remote-sensing scientist Stef Lhermitte of Delft University of Technology in the Netherlands. That record only goes back to 2000, but it could well turn out to be the biggest wildfire in Greenland’s history. The fire, first spotted by a pilot on 31 July, has taken researchers by surprise. His initial analysis of satellite observations suggests there have been a few small wildfires in Greenland since 2000 but that over the past three years there has been a huge increase in the area burning.
No doubt then that our house is burning. The question now is: where are we looking?
Canada wildfires from space and ground – Seeing beyond the flames: a series of observations here
Wildfires in French Mediterranean region observed from MODIS here
This is good news! The collaboration between all European countries is of great importance to continue to ensure major step forwards in Earth observation scientific studies using satellite measurements. And the statement of UK to stay within European Union’s Copernicus Earth observation programme after Brexit is therefore more than welcome!
Check out the article here from Eva Stierman, our GRS – TU Delft student, doing a measurement campaign along the Dutch monitoring lines for validating the water quality products delivered by satellite observations.
Eva is doing her Master thesis at Rijkswaterstaat (RWS) & DELTARES, with GRS – TU Delft, to validate Sentinel-3A OLCI level-1 and level-2 data products with in situ measurements of RWS. She recently left, from the harbor of Scheveningen, for a measurement campaign at several locations in the north of the Netherlands: the Rottumerplaat, Terschelling and Noordwijk monitoring lines.