Lately, you can read the term zombie fire in more and more media articles. A new way to gain views, or a real thing?

A guest blog post by Pierre Markuse

Zombie fires is a catchy name you can read in more and more articles and headlines in the media. With a reason, it attracts attention.

Now, before we begin to discuss whether zombie fire is a fitting name or more of an attraction-grabbing clickbait-naming we should take a look at what is usually described as a zombie fire.

What is it?

It all begins with an initial wildfire. Important in this case is that for it to become what is sometimes called a zombie fire it has to start in, or spread into an underground peat layer (or surface peat layer and be covered up by snow in winter). In these layers, the fire continues as smouldering combustion (Rein, 2013), without visible flames and, depending on the depth of the fire with lots of smoke visible or almost no visible smoke at all at the surface level. The fire then spreads, not only deeper into the ground, but also laterally following the pipe network within the peat layer, which allows enough oxygen to reach the fire and keep it alive. However, while there is enough oxygen to keep the fire alive, the fire will spread at a much lower speed underground or under snow cover, because the supply of oxygen is limited now. Depth-wise the fire is limited by the water table, laterally it could continue slowly burning through the complete peat layer. At times, following the pipe network, the smouldering fire can resurface and, given the right conditions, initiate a new flaming surface fire, even distant from the original starting point of the fire.

Acting like a zombie…

Since the fire might not be seen while burning underground the name zombie fire is being used by some to describe those fires. A fire starts, apparently dies, but then reappears, sometimes even distant from its original location. Just like a zombie coming back to “life”. This can happen days or even months after apparently dying down in the original location. This way fires can smoulder during the winter (hidden by a snow cover or in an underground peat layer) and then reappear on the surface months later, when the winter is over and conditions are more favourable for surface fires again.

Take a look at this illustration, explaining the spread of underground smouldering fires.

Zombie fire or no zombie fire?

Now that we know what we are talking about, is the name zombie fire fitting and can be used, or should it be avoided?

I asked the fire community on Twitter and this was the result.

 — @Pierre_Markuse

As you can see 39% say it should be avoided. However, the majority believes the name to be either perfectly fine or while acknowledging its clickbait nature, find it suitable to use in this case.

Here are two opinions in favor of the name:

 — @GuillermoRein

 — @DrTELS

Attention is key

And while I’m not a big fan of the name zombie fire I have to agree. Getting science into mainstream media is hard enough. Zombie fire might sound laughable to some, but it garners attention and that initial attention might get people to read an article they otherwise would have not read, and that is always a win.

Those tweets are all from the same thread, you should read the whole discussion, also talking about another controversial moniker, the “megafire”.

But coming back to our zombie fire, what names are there?

 — @Pierre_Markuse

Many names

Some would call it a holdover fire, which is correct but sounds a bit static, it seems to not include the spatial component, that a smouldering underground fire could extent laterally and pops up in a new surface location. I would say the same is true for the terms sleeper fire and the most-chosen overwintering (or over-wintering) fire. You could of course always just describe it as what's it is, a smouldering fire, however, not all smouldering fires are necessarily of the type that seems to disappear and reappear. Some of them burn, and sometimes quite visibly producing lots of smoke, through a peat landscape and that’s it.

In the end, everybody will use the name they are most familiar, and most in agreement with. Another reason why we should not expect the tern zombie fire to die out, as, for media, it will most certainly work best of all alternatives.

Why the sudden amount of zombie fire mentions in media?

Holdover fires are nothing new. Peatlands are known for them and landscapes within and around the Arctic Circle often have large areas of peat.

You might remember that last year the fire season within and around the Arctic Circle was a pretty active one. Just because of the number of fires we had last year, the chances for some of them turning into holdover fires in the peatlands in which they were burning is bigger than during a normal fire season. Add to that the warm winter and the recent heatwave in Siberia and you get the conditions for those holdover fires to reappear and keep on burning through the peatlands or initiate new flaming fires in the areas. This is why scientists believe that at least some of the fires we are seeing right now are holdover fires.

Take a look comparing the fire season in the Sakha Republic, Russia, this May to last year and the mean of 2003–2018. While it is too early in the fire season to make predictions, you can see that 2020 is for now on a good way to be an active season.

This image here, also showing 2019 and 2003–2018 data for the month of June makes clear why it is still a bit early to tell how things will develop, as usually most of the fires happen later in the year.

Why are Arctic wildfires dangerous?

While the temperatures on Earth are rising, wildfires within the Arctic Circle and regions just south of it are becoming more and more likely. This is dangerous because those fires often affect peatlands and not only add to the amount of carbon dioxide in the atmosphere (carbon dioxide which up until now has been stored in healthy peatlands) but peat fires also release methane, a far more potent greenhouse gas than carbon dioxide, accelerating the greenhouse effect, leading to rising temperatures and even more fires.

Depending on where in the Arctic, fires can be cause for another problem. Burn scars in the arctic can persist for quite some time before completely recovering, possibly changing the type of vegetation and facilitating the degradation of ice-rich permafrost (Jones et al., 2013), for example by decreasing the ground surface albedo, and therefore increasing the amount of energy absorbed, leading to higher surface temperatures. While frozen, the permafrost works as a storage for carbon monoxide and methane, but once thawing, it releases the stored greenhouse gases into the atmosphere, contributing to global warming.

Remote locations make it hard to battle fires

Another reason why fires in the Arctic are a problem is the fact that the Arctic regions are big and very remote. Even if detected, fire-fighting equipment is usually far away and often regions don’t even have streets. In Russia, many fires in Siberia will just burn until dying down naturally.

The problems with detecting holdover fires

Holdover fires are burning under snow cover and maybe even in underground peat layers. Directly detecting those fires using remote sensing satellites is almost impossible, the temperature differences at surface level are usually too small and localized for satellites to pick them up. However, at least some overwintering holdover fires can be classified using an algorithm for overwintering holdover detection. (Scholten and Veraverbeke, 2020) This allows us to classify a fire as overwintering holdover fire when it reappears, but it will still be invisible to remote sensing satellites until this happens.

Other methods of directly finding holdover fires (while still underground or snow cover) following bigger wildfires are more promising to find them, especially using infrared sensors with higher spatial resolution and sensitivity from planes and helicopters, as well as screening burn scars on foot using infrared sensors. Once located, it could then be possible to extinguish the fire, preventing it from reappearing again. Of course, these methods are more expensive and again hindered by the fact that a lot of Arctic wildfires are in remote locations.

Using the Sentinel Hub EO Browser to find and image wildfires

If you are interested in finding and imaging wildfires yourself, I recommend using the Sentinel Hub EO Browser. Its presets allow for quick results, and once accustomed to it, you can use custom scripting for even better results.

Should you be completely new to the EO Browser, reading “Remote Sensing in the Classroom — Getting Started Guide” will help you get started. While meant to get teachers to use it in the classroom, it lists a lot of resources that will help you to get going with your own images and scripts.

If you already know your way around the EO Browser, reading “Looking at Wildfires (and more…) — An Introduction” and “Visualizing Wildfires and Burn Scars with the Sentinel Hub EO Browser V2” might help you to specifically image wildfires using the EO Browser.

References

Jones, Benjamin M., Amy L. Breen, Benjamin V. Gaglioti, Daniel H. Mann, Adrian V. Rocha, Guido Grosse, Christopher D. Arp, Michael L. Kunz, and Donald A. Walker. “Identification of Unrecognized Tundra Fire Events on the North Slope of Alaska.” Journal of Geophysical Research: Biogeosciences 118, no. 3 (September 24, 2013): 1334–44.
https://doi.org/10.1002/jgrg.20113.

Rein, Guillermo. “Smouldering Fires and Natural Fuels.” Edited by C. M. Belcher. Fire Phenomena and the Earth System, September 2013, 15–34. John Wiley & Sons, Ltd, 2013.
https://doi.org/10.1002/9781118529539.ch2.

Rein, Guillermo and E. Burns. “Illustration of a smouldering peat fire initiated by flames in the surface” from “Smouldering Fires and Natural Fuels.” Edited by C. M. Belcher. Fire Phenomena and the Earth System, September 2013, 15–34. John Wiley & Sons, Ltd, 2013. https://doi.org/10.1002/9781118529539.ch2.

Scholten, Rebecca, and Sander Veraverbeke. “Spatiotemporal Patterns of Overwintering Fire in Alaska.” Fire Science Highlights Blog. Alaska Fire Science Consortium, April 8, 2020. https://akfireconsortium.wordpress.com/2020/03/25/spatiotemporal-patterns-of-overwintering-fire-in-alaska/.

I would like to thank Guillermo Rein and Mark Parrington for their help, as well as all people who contributed to my Twitter poll regarding the zombie fire name.

Pierre Markuse

Pierre Markuse is a freelance remote sensing expert and blogger with a special interest in optical remote sensing, his images being used by numerous media outlets.

How to make satellite images more approachable to the general public, communicating scientific backgrounds, and the usage of satellite images in journalism are additional fields of interest.

You can read more of his work on his personal blog here or take a look at his satellite images here on Flickr.

“Zombie” Fires in the Arctic— Clickbait or real? was originally published in Sentinel Hub Blog on Medium, where people are continuing the conversation by highlighting and responding to this story.

More and more satellite images find their way into media publications, which means more information for the audience, including more false information

A guest blog post by Pierre Markuse

Thanks to an ongoing shift in data policies, more and more satellite data is available for free and — more or less — easily accessible. Data from a diverse range of satellites can be downloaded, and in most cases used without restrictions. So why not have a look?

A lot of media outlets are making ample use of those satellite images and data. Not only open data policies but also services like the Sentinel Hub EO Browser are making it easy for even small newsrooms or single journalists to get the latest satellite data and use the images created from it.

However, the people using satellite imagery from other sources or maybe even creating their own, aren’t always trained in doing so, which of course can lead to some mistakes. Those mistakes are usually not a problem for a private user doing some research, but for a journalist who is going to publish the images it is a problem, especially when the images are used as a source or proof of some aspects of their story.

An example

Let us take a look at the following image, taken by Landsat 8.

Admiral Kuznetsov

The image is showing the Russian aircraft carrier Admiral Kuznetsov (or “Admiral Flota Sovetskogo Soyuza Kuznetsov” to be complete) and some support vessels in the Mediterranean Sea.

This is one of the cases in which not a mistake in the interpretation of a satellite image could lead to a mistake, but a lack of further information that could explain why we are seeing what we are seeing. It should also show you that, whatever you might be seeing in a satellite image, you should not immediately draw conclusions, as there are almost always more explanations for why you are seeing, what you are seeing.

So what are we seeing? Well, if you take a look at the close-up in the upper right corner of the image you can see the Admiral Kuznetsov with a pretty large amount of what appears to be smoke coming from it. Actually, the smoke cloud produced is over a kilometer in length. I would assume pretty much every journalist would see it this way, and they would be right, it is indeed a big cloud of smoke.

Without any further information, journalists could now draw a lot of conclusions. The vessel could be on fire. Maybe an accident? Maybe an exercise? Maybe even battle damage? The resulting satellite image would indeed look quite similar.

Mazut

However, in this case the reason is a pretty mundane one, the Admiral Kuznetsov has a rather out of date propulsion system and is still (at least at that time) burning Mazut, a low quality fuel oil that, in combination with the old technology used, is producing a lot of smoke.

In the case of this aircraft carrier image, mistakes are most likely to be made because of a lack of context. However, while the initial interpretation of smoke is correct, a more advanced user of satellite imagery could have then taken at look at the infrared bands and would have seen there are no emissions that would support a fire. That would still be no confirmation that there was no battle damage but it should lead them to look for other explanations.

The next example is an often-repeated one, and while it has no tragic consequences it still is a mistake that is conveyed to audiences again and again.

The above image of the Camp Fire in California looks as if it would be showing actual flames. However, what is looking like flames here are just zones that emit more infrared radiation, indicating heat. Those hot spots usually align quite well with active fires or zones with lots of residual heat, as you can see from the smoke emanating from those zones. Showing the IR radiation in that way is an artistic choice which can make images like those more interesting.

In case you are wondering, the image without mixed in infrared radiation looks like this.

It is important to communicate those things to the people the image is intended for. And for that at least some expertise is necessary in the newsrooms. I wrote about this in more detail on my personal blog in my post “Satellite Image Guide for Journalists and Media”. The post will also give you some tips to get you started with using satellite images.

And another example of the same kind

In this image you can the the lava flows of the Kilauea Volcano glowing red-orange. Well, actually, you can’t. While the lave flows were indeed glowing in some places, the glow was not really visible in natural-color images from space. This image again mixes visible light and infrared radiation, showing the latter in orange-red. It makes for a beautiful visualization but that again should be communicated.

More tricky

But it can get even more tricky than this. Just by talking to the person who created the images of above kind journalists could avoid mistakes. But now it gets really hard, take a look at this animation made from Sentinel-2 images.

In these images we can see the Mayak Fissile Material Storage Facility (FMSF) in Russia. The Mayak site was the possible source of an increase in airborne radioactivity in Europe in the autumn of 2017. These images are showing that some work is done at the facility including at the end of September when the radioactivity was detected. It is, however, almost impossible to really say what is happening here, higher resolution images would be needed, and even with those it is not always possible to say what is going on.

As you can see, just having access to satellite images doesn’t immediately answer all your questions. Sometimes it will be hard to see what is actually going on, and even if you can see it, there still might be more explanations for it than just one, and additional information will be needed to get the whole picture. Still, even when not showing the whole picture, imagery can be helpful to get a new angle on a story or explore possibilities.

Not always easy, but possible…

And while it is not always easy to interpret and use satellite images, it is certainly possible and can be a vast source of information for journalists. Not only can they make their stories more visual, no, they can use satellite imagery as source and proof for their stories.

The above image from Planet Labs is a good example of a high resolution image, you can see damaged structures (especially in the lower half) as well as a camp made up of tents in the upper left corner. Images like these can help in making a story more visual or even be a crucial part of getting a story together.

High resolution images are not always free of costs, but are in some cases needed to really get to the bottom of things from high above.

Still, we can learn a lot from medium resolution images, take a look at the following image, taken by Sentinel-2.

The above image is showing how Sentinel-2 imagery can be useful in environmental monitoring and journalism. Higher resolution is not really needed here, the image is showing what is going on. The burning oil wells were highlighted using a custom script in the EO Browser.

You should read “Environmental Monitoring of Conflicts using Sentinel-2 data” by Wim Zwijnenburg to get a few more examples of what can be done with satellite images when it comes to journalism.

And don’t underestimate what the Sentinel-2 satellites can actually distinguish. Do you remember the Admiral Kuznetsov image from the beginning? It was taken by Landsat 8 with a 15-meter resolution. Now take a look at this image of the Admiral Kuznetsov, taken by Sentinel-2A with 10-meter resolution. Make sure to click the Flickr link and download it in full resolution. As you can see, 10-meter resolution is enough to identify the vessel.

Expertise in newsrooms

Assuming, and this scenario seems likely, that the usage of satellite images in newsrooms will just become more prevalent from here on out, media outlets have to make sure to have people who know what they are doing. This could be journalists who have acquired that expertise or dedicated remote sensing experts, the latter probably only be feasible in larger media outlets.

Depending on what is being done, the amount of training needed to create useful images for journalistic usage may vary. Already quite a few journalists are making good use of satellite images. Just have a look at these examples here: One - Two - Three - Four

Journalistic use of the Sentinel Hub EO Browser

Having said so much about journalism and satellite images I would like to again recommend the EO Browser and hope that journalists will give it a try. Get a free account today!

It offers an easy to use interface and comes with a preset of useful band combinations which make it easy to get started.

Supporting the usage of satellite images in journalism

Additionally, all images created with the EO Browser or the Sentinel Hub Playground can freely be used in media publications (CC BY 4.0 licensed), so there is no hassle about publication rights or time lost to get usage permission. More information on the Sentinel Hub Journalism pages, also offering some more examples of satellite image use in articles.

You should also check out the Sentinel Hub Education pages to get some more information about remote sensing, especially when you are just starting using satellite images.

Opportunity for the GIS and remote sensing community

In his aforementioned blog post Wim Zwijnenburg said:

There is also an opportunity for the GIS community to educate a broader audience, consisting of civil society organisations working on land rights, natural resources, environment, human rights, disarmament and conflicts to utilize the data available.

I wouldn’t just limit it to civil society organisations but keep it at “a broader audience”, consisting of the general public and especially journalists.

While the access to satellite images and data got a lot easier during the last years, there is a bit of a lack of good information for beginners on how to get started and how to interpret satellite images. Information can be found in snippets of different sizes all over the web, but it would be nice to see more resources in one place. Initiatives such as the Sentinel Hub Education pages are a good start, but there is still some work to do.

Pierre Markuse

Pierre Markuse is a freelance remote sensing expert and blogger with a special interest in optical remote sensing, his images being used by numerous media outlets.

How to make satellite images more approachable to the general public, communicating scientific backgrounds, and the usage of satellite images in journalism are additional fields of interest.

You can read more of his work on his personal blog here or take a look at his satellite images here on Flickr.

Why Newsrooms need People with Expertise in Remote Sensing was originally published in Sentinel Hub Blog on Medium, where people are continuing the conversation by highlighting and responding to this story.

You talk about showing your political profile in your social media. For a long time I tried not to. My followers are, as far as I can tell, mostly on the more liberal side of the spectrum. It seemed like preaching to the choir for me. Lately however, I started to include, retweet, and like some political tweets because staying silent felt just wrong. Most of my political tweets go pretty much unnoticed or ignored by my followers. Yet, every now and then my opinion leads to me losing a few followers. I don’t care that much about the number of them, but sometimes I have to ask myself whether some of them really harbour ideologies and worldviews so harshly different from mine, that they feel the need to unfollow me for voicing an opinion. This concerns me a lot more than being called ‘snowflake’ the umpteenth time.

I will continue to include the occasional political tweet if I feel the need to speak up. I will not be silenced by bullies or political trolls. I do however understand that some people don’t feel like being able to do this, be it for professional considerations or because of mental health reasons.

since you are using GIMP anyway, you could skip the Imagemagick step. Just open the three bands in GIMP and then in the menu use Colors → Components → Compose and assign your bands to the color channels, resulting in a color image.

After doing that you can then use GIMP to adjust levels and curves, sharpening, and whatever else you want to do. This will also save you from having to try finding the right values for the levels like you do now with Imagemagick, since GIMP allows you to more or less instantly see the changes when you adjust the sliders.

You describe Hillary as a disappointing Democrat and I agree with that. Voting for Hillary will bring America four, maybe even eight years with very little change. Yes, here and there might be some tweaks to the system but in general you will not see big reforms.

Now Trump is dangerous. Not as dangerous as Cruz as President would have been, but Trump is dangerous because he just has no plan for America. Instead of building a wall, he will hit a wall, full speed. And he will only see that after it’s done.

But maybe, just maybe, this would also be a chance. After four years of Trump with horrible results people might be more open to change. Open to vote for somebody who actually knows what he/she is doing. Open for much needed reforms. Maybe. Then again, never underestimate the stupidity of people.

Yes, the situation will slowly get better with better training for law enforcement officers but will better training really end the problem? The legal system is just one of the many facets of the problem. What America needs is a better education for children and young adults regarding social disparities, an education focusing on the problems minorities experience and also focusing on tolerance. An education based on science, showing that people of any origin are not inherently worse than white Americans. Then and only then there is a chance that younger generations will not mindlessly accept and take on their parent’s latent racism but that racism might slowly die out.

Laws can help streamlining the process, but without really changing what people believe there will always be disparities, some minor, some big, some open, some hidden.

Because the U.S. did not have strict gun laws for so long, there are countless guns in circulation. Even introducing stricter gun laws right now wouldn’t make those guns disappear. Yes, open and concealed carry (to a lesser degree) could be stopped but getting all the guns would be almost impossible.

Even worse: With 3D-printers getting more and more sophisticated and cheaper, it is now possible to produce your own and unregistered guns. Right now very few people might do that, but stricter laws would certainly make that a more regular occurrence.

So yes, something has to be done, the U.S. do need stricter gun laws, but they should be prepared that it might take a long time to see the full effect of stricter guns laws and have the patience to see the results. And then there is also the mindset of many Americans, equating guns with safety and freedom. With people connecting those things in their mind it is of course harder to regulate guns because attempts to do so will make politicians lose votes. Luckily this mindset seems to be fading, opening up possibilities to actually enact stricter laws.