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Imaggeo on Mondays: Fuelling the clouds with fire

30 Jun

Wildfires frequently break out in the Californian summer. The grass is dry, the ground parched and a small spark can start a raging fire, but burning can begin even when water is about. Gabriele Stiller sets the scene for a blaze beside Mono Lake, exploring the events that got it going and what it may have started in the sky… 

While on shores of Mono Lake in the summer of 2012, I spotted something strange in the distance: a great blaze on the other side of the lake. We were on a trip through the southwestern states (a long tour through California, Nevada, Utah and Arizona). All the days before we had been continuously accompanied by thunderstorms that broke out during the afternoon. The photo was taken before the daily thunderstorm, and the large convective system already hinted to the next storm to come – and indeed it did, just a few hours later.

Desert fires close to Mono Lake, California. (Credit: Gabriele Stiller via imageo.egu.eu)

Desert fires close to Mono Lake, California. (Credit: Gabriele Stiller via imageo.egu.eu)

It was not clear if this convective cloud system was generated by uplift of heated air initiated by the fire, a process known as pyro-convection, or if it was simply a coincidence. After all, thunderstorms were a regular occurrence throughout our trip. This could have been the storm of the day, and the related convection could have transported the air and smoke from the fire upwards. Or a combination of both could have been behind it. The cumulus cloud was quite isolated, with clear sky surrounding it, but you can already see a small anvil developing (the area where ice is formed in the cloud) above the cauliflower-like cumulus – a hint towards a developing thunderstorm. Such a development would make the cloud into a cumulonimbus cloud.

So what caused the blaze? On 8 August 2012, the wildfire was started through lightning ignition by a thunderstorm coming from the Sierra Nevada, and it burned for several days on open grassland, far from human infrastructure. Due to these circumstances, firefighting was not particularly difficult for the authorities. However, more than 13000 acres were burned, and more than 500 people fought the fire. One of the priorities was to keep the amount of sage-grouse habitat burned to a minimum.

By Gabriele Stiller, Karlsruhe Institute of Technology, Karlsruhe, Germany

Imaggeo is the EGU’s open access geosciences image repository. Photos uploaded to Imaggeo can be used by scientists, the press and the public provided the original author is credited. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. You can submit your photos here.

Imaggeo on Mondays: A marvellous moving image

5 May

Every year, in association with our annual General Assembly, we run a photo contest to feature and celebrate fantastic geoscience images. Last year we introduced a moving image component to the competition, giving photographers the chance to submit short clips of great geoscience footage. Here’s this year’s highly commended entry by Matthias Buschmann…

Svalbard’s stunning scenery (Credit: Matthias Buschmann via imaggeo.egu.eu)

Every travel opportunity is a chance to capture something beautiful on camera, whether it’s a marbled road-cut as you pause on a long journey, a look up through the trees on your way to work, or a glimpse at the land below as you fly to a far-flung location. The latter is what led Matthias Buschmann, a PhD candidate from the University of Bremen, to steal a few seconds of stunning Svalbardscape on camera.

Twice a week a small passenger plane brings cargo and keen scientists to the remote village of Ny Ålesund, Svalbard. On a mission to measure atmospheric trace gases from a joint French-German research base (AWIPEV), Buschmann stepped aboard, ready to capture data for a number of global atmospheric projects (the Total Column Observing Network and the Network for the Detection of Atmospheric Composition Change), but that wasn’t all he captured on the trip.

Buschmann directed his camera out to the scene below, hit record, and – voila! – One lovely landscape for other eyes to see. He describes the scene: “Looking in north-eastern direction, the flight in this clip covers the outskirts of Ekmanfjorden, a northern branch of Isfjorden. The glacier we see beneath is called Sefströmbreen and, finally, the mountain range Palatiumfjellet with its Svalbard-characteristic shapes. We were really lucky to have such great weather after a couple of rather cloudy days”.

Imaggeo is the EGU’s open access geosciences image repository. Photos uploaded to Imaggeo can be used by scientists, the press and the public provided the original author is credited. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. You can submit your photos here.

Imaggeo on Mondays: Exploring the East African Rift

10 Mar

This week’s Imaggeo on Mondays is brought to you by Alexis Merlaud, an atmospheric scientist from the Belgian Institute for Space Aeronomy. While the wonders of the African atmosphere feature in his photography, the East African Rift has a much bigger tale to tell. Drawing from all aspects of geoscience Alexis shares its story…

Kilimanjaro from Mount Meru. (Credit: Alexis Merlaud, distributed via imaggeo.egu.eu)

Kilimanjaro from Mount Meru. (Credit: Alexis Merlaud, distributed via imaggeo.egu.eu)

This picture shows Kilimanjaro, Africa’s highest mountain, at sunrise. It was taken from Socialist Peak, which marks the top of Mount Meru, some 70 km to the southwest. Both mountains are located in Tanzania and are among the largest stratovolcanoes of the East African Rift Zone. Unlike Kilimanjaro, Meru is active and its most recent eruption occurred in 1910.

Stratovolcanoes, also called composite cones, are built-up by alternating layers of lava flows, pyroclastic rocks, and volcanic ash. During a large eruption, huge quantities of ash and sulphur dioxide can reach the stratosphere, where they can affect the climate for several years, as did the eruptions of Krakatau in 1883 and Pinatubo in 1991. Sulphur dioxide is converted to sulphuric acid droplets, which spread with the ashes throughout the stratosphere. These aerosols screen some of the sunlight, decreasing the average surface temperature by about one degree. The temperature in the stratosphere simultaneously rises by a few degrees, due to the enhanced absorption of sunlight by aerosols.

There is a difference in the tectonic processes associated with these South East Asian volcanoes and the East African Rift: the former are located above a subduction zone while the rift is a divergent boundary.  An example of large volcanic eruption in a divergent zone is the Laki (Iceland) eruption in 1783, which yielded severe meteorological conditions and reduced harvests for several years in Europe. This eruption may have also helped trigger the French Revolution in 1789.

Plate tectonics in East Africa created Kilimajaro and have also played a role in early human evolution, by shaping the local landscape and the long-term climate, thus modifying the environment of our ancestors. East Africa is the area in the world where most of the hominid fossils have been discovered, including Homo sapiens – the oldest fossil record is 200,000 years old and started to move out from Africa 100,000 years ago!

A final thanks: thanks Cristina Brailescu for help climbing Meru and Emmanuel Dekemper for support on editing the picture. 

By Alexis Merlaud, Belgian Institute for Space Aeronomy

Imaggeo is the EGU’s open access geosciences image repository. Photos uploaded to Imaggeo can be used by scientists, the press and the public provided the original author is credited. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. You can submit your photos here.

Geoscience under the tree

18 Dec

In a festive-themed post, EGU Media and Communications Manager Bárbara Ferreira selects a plethora of geoscience-inspired Christmas presents, which you could give to your favourite researcher. Please note that, with the exception of the last one, the items listed below are not necessarily recommended or endorsed by the EGU.

For me Christmas is more about eating large amounts of food and celebrating with family and friends than it is about giving and receiving presents. But I am guessing many of the readers of this blog are still scratching their heads thinking what gifts to get to the geoscientists in their families, to their Earth or space science researcher friends or, why not, themselves. This, and the fact that Paleoseismicity posted about some beautiful geology shoes a few days ago, is why I’ve set out to discover the best geoscience-inspired gift items out there.

Compiling this list ended up being easier than I thought because a few people, such as Georneys’ Evelyn Mervine and Agile’s Matt Hall have written similar blog posts in the past. And also because I discovered that Etsy – the e-commerce website for all things handmade or vintage – has an impressive collection of geoscience-y items. So, brace yourselves for a link-rich post!

Solid Earth

I’ll start with a present idea for our crafty readers: if you are into knitting, or know someone who is, this book filled with knitted-dinosaur patterns might be for you. If you’re not crafty, you may prefer to gift this triceratops cup or a pair of agate bookends, or even this t-shirt with a different take on the Earth’s internal structure. The geomorphologist in your life might like this antique map illustrating the geomorphology of the Alpine region or this simple yet beautiful travel journal.

If, instead, volcanology is your thing, then you might like this awesome volcano woolly hat – and if you are looking for a gift for a little one, this wooden volcano stacker could be your choice. For soil scientists, Etsy has a collection of beautifully illustrated soil postcards, while tectonic scientists and seismologists, may find this t-shirt funny. This science kit would suit a young fan of rocks and minerals, while this tie with crystalline formations would be more appropriate for a grown up.

Volcano hat by MariaBjork

Volcano hat by MariaBjork

Soft Earth

Moving on to soft-Earth disciplines, atmospheric scientists might like this wonderful screen print of different types of clouds, or this original necklace representing the various layers of the Earth’s atmosphere. And there’s this rather neat calendar of the sky and sea, which may also please ocean scientists. These researchers might also like an ocean tide ceramic pot or a 19th century map of the Atlantic Ocean.

Budding hydrologists, on the other hand, may be fascinated by this hydropower kit, while older ones will likely appreciate this antique engraving of water engineering. On the topic of antiques, the climate scientist in your life may like this climate map of Europe or this beautifully illustrated book to teach kids about climate. When gifting biogeoscientists, you can’t go wrong with this fantastic diatoms t-shirt (available for men and women) or these seaweed magnets.

Diatoms t-shirt by vortextradingcompany

Diatoms t-shirt by vortextradingcompany

Space and planetary science

Moving up into the upper atmosphere, your favourite solar-terrestrial scientist might like to receive this rather cute card of aurora in the Arctic or, for something a bit different, this pair of Northern Lights leggings! Going further up into space, the Earth’s magnetosphere finds its way into this totebag/backpack while the solar corona is the star of this antique print.

Planetary scientists also have plenty to choose from, with a variety of art decals and solar system charts available on Etsy. There is even a seller who builds jewellery with photos from NASA missions, such as this Mars Curiosity Rover pendant. Budding space and planetary scientists will likely be happy with this space exploration kit from National Geographic.

Interdisciplinary areas

Moving on to the more interdisciplinary areas of the EGU, I couldn’t help but mention Slow Factory, who produce stunning (but expensive!) clothing items from satellite images: the Terra MODIS Greenland dress and this silk square with an image of phytoplankton from the Bay of Biscay are two of the highlights. For something a bit more affordable, you could gift this top to bottom poster from Our Amazing Planet or this carbon cycle t-shirt. If you are feeling crafty, you can get LEGOs to build this rather incredible LEGO globe. Energy, resources and the environment enthusiasts have plenty to choose from, from a sustainable Earth lab or a solar-powered night light to a pair of windmill earings or a wind-energy decal. If great waves are more your thing, you may be interested in this tsunami top or, if landslides are your natural-hazard of choice, in this interesting pendant.

If you, like me, prefer to give and receive an experience as a gift, then why not offer a geoscientific trip? Though I haven’t been on a trip of this kind myself, I found a few companies that organise geo-themed excursions, such as this one in Italy, this one in Iceland or this one for trips further afield.

Finally, I couldn’t finish this blog post without suggesting the best present of them all (OK, I’m biased!). This Christmas, why not gift EGU memberships to the Earth, planetary and space scientists in your life? It is very affordable and researchers will likely appreciate the discounted registration rate members receive to the EGU General Assembly!

By Bárbara Ferreira, EGU Media and Communications Manager

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