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August GeoRoundUp: the best of the Earth sciences from around the web

August GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, as well as unique and quirky research news, this monthly column aims to bring you the best of the Earth and planetary sciences from around the web.

Major Stories

On August 25th Hurricane Harvey made landfall along the southern coast of the U.S.A, bringing record breaking rainfall, widespread flooding and a natural disaster on a scale not seen in the country for a long time. In fact, it’s the first time since 2005 a major hurricane has threatened mainland U.S.A. – a record long period.

But Harvey’s story began long before it brought destruction to Texas and Louisiana.

On August 17th,the National Space Agency (NASA) satellite’s first spotted a tropical depression forming off the coast of the Lesser Antilles. From there the storm moved into the eastern Caribbean and was upgraded to Tropical Storm Harvey where it already started dropping very heavy rainfall. By August 21st, it had fragmented into disorganised thunderstorms and was spotted near Honduras, where heavy local rainfall and gusty winds were predicted.

Over the next few days the remnants of the storm travelled westwards towards Nicaragua, Honduras, Belize and the Yucatan Peninsula. Forecasters predicted that, owing to warm waters of the Gulf of Mexico and favorable vertical wind shear, there was a high chance the system could reform once it moved into the Bay of Campeche (in the southern area of the Gulf of Mexico) on August 23rd. By August 24th data acquired with NASA satellites showed Harvey had began to intensify and reorganise. Heavy rainfall was found in the system.

Harvey continued to strengthen as it traveled across the Gulf of Mexico and weather warnings were issued for the central coast of Texas. Citizens were told to expect life-threatening storm surges and freshwater flooding. On August 25th, Harvey was upgraded to a devastating Category 4 hurricane, when sustained wind speeds topped 215 kph.

Since making landfall on Friday and stalling over Texas (Louisiana is also affected) – despite being downgraded to a tropical storm as it weakened – it has broken records of it’s own. “No hurricane, typhoon, or tropical storm, in all of recorded history, has dropped as much water on a single major city as Hurricane Harvey is in the process of doing right now in Houston (Texas)”, reports Forbes. In fact, the National Weather Service had to update the colour charts on their graphics in order to effectively map it. This visualisation maps Harvey’s destructive path through Texas.

A snaptshot from the tweet by the official Twitter account for NOAA’s National Weather Service.

So far the death toll is reported to be between 15 to 23 people, with the Houston Police Chief saying 30,000 people are expected to need temporary shelter and 2,000 people in the city had to be rescued by emergency services (figures correct at time of writing).

Many factors contributed toward making Hurricane Harvey so destructive. “The steering currents that would normally lift it out of that region aren’t there,” J. Marshall Shepherd, director of the atmospheric sciences program at the University of Georgia, told the New York Times. The storm surge has blocked much of the drainage which would take rainfall away from inland areas. And while it isn’t possible to say climate change caused the hurricane, “it has contributed to making it worse”, says Michael E Mann. The director of the Earth System Science Center at Pennsylvania State University argues that rising sea levels and ocean water temperatures in the region (brought about by climate change) contributed to greater rainfall and flooding.

A man carries his cattle on his shoulder as he moves to safer ground at Topa village in Saptari. Credit: The Guardian.

While all eyes are on Houston, India, Bangladesh and Nepal are also suffering the consequences of devastating flooding brought about a strong monsoon. The United Nations estimates that 41 million people are affected by the disaster across the three countires. Over 1200 people are reported dead. Authorities are stuggling with the scale of the humanitarian crisis: “Their most urgent concern is to accessing safe water and sanitation facilities,” the UN Office for the Coordination of Humanitarian Affairs (OCHA) said earlier this week, citing national authorities. And its not only people at risk. Indian authorities reported large swathes of a famous wildlife reserve park have been destroyed. In Mumbai, the downpour caused a building to collapse killing 12 people and up to 25 more are feared trapped.Photo galleries give a sense of the scale of the disaster.

Districts affected by flooding. Credit: Guardian graphic | Source: ReliefWeb. Data as of 29 August 2017

What you might have missed

In fact, it’s highly unlikely you missed the coverage of this month’s total solar eclipse over much of Northern America. But on account of it being the second biggest story this month, we felt it couldn’t be left out of the round-up. We particularly like this photo gallery which boasts some spectacular images of the astronomical event.

This composite image, made from seven frames, shows the International Space Station, with a crew of six onboard, as it transits the Sun at roughly five miles per second during a partial solar eclipse, Monday, Aug. 21, 2017 near Banner, Wyoming. Credit: (NASA/Joel Kowsky)

Since the end of July, wildfires have been raging in southwest Greenland. While small scale fires are not unheard of on the island otherwise known for its thick ice cap and deep fjords, the fires this month are estimated to extend over 1,200 hectares. What started the fires remains unknown, as do the fuel sources and the long-term impacts of the burn.

The U.S.A’s National Oceanic and Atmospheric Administration highlighted that the fires are a source of sooty “black carbon”. As the ash falls on the pristine white ice sheet, it turns the surface black, which can make it melt faster. Greenland police recently reported that unexpected rain haf all but extinguished the massive fires; though the situation continues to be monitored, as smouldering patches run the risk of reigniting the flames.

 

 

 

Links we liked

The EGU story

Do you enjoy the EGU’s annual General Assembly but wish you could play a more active role in shaping the scientific programme? Now is your chance! Help shape the scientific programme of EGU 2018.

From today, until 8 Sep 2017, you can suggest:

  • Sessions (with conveners and description), or;
  • Modifications to the existing skeleton programme sessions
  • NEW! Suggestions for Short courses (SC) will also take place during this period
  • From now until 18 January 2018, propose Townhall and splinter meetings

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

 

GeoSciences Column: Is smoke on your mind? Using social media to assess smoke exposure from wildfires

GeoSciences Column: Is smoke on your mind? Using social media to assess smoke exposure from wildfires

Wildfires have been raging across the globe this summer. Six U.S. States, including California and Nevada, are currently battling fierce flames spurred on by high temperatures and dry conditions. Up to 10,000 people have been evacuated in Canada, where wildfires have swept through British Columbia. Closer to home, 700 tourists were rescued by boat from fires in Sicily, while last month, over 60 people lost their lives in one of the worst forest fires in Portugal’s history.

The impacts of this natural hazard are far reaching: destruction of pristine landscapes, costly infrastructure damage and threat to human life, to name but a few. Perhaps less talked about, but no less serious, are the negative effects exposure to wildfire smoke can have on human health.

Using social media posts which mention smoke, haze and air quality on Facebook, a team of researchers have assessed human exposure to smoke from wildfires during the summer of 2015 in the western US. The findings, published recently in the EGU’s open access journal Atmospheric Chemistry and Physics, are particularly useful in areas where direct ground measurements of particulate matter (solid and liquid particles suspended in air, like ash, for example) aren’t available.

Particulate matter, or PM as it is also known, contributes significantly to air quality – or lack thereof, to be more precise.  In the U.S, the Environment Protection Agency has set quality standards which limit the concentrations of pollutants in air; forcing industry to reduce harmful emissions.

However, controlling the concentrations of PM in air is much harder because it is often produced by natural means, such as wildfires and prescribed burns (as well as agricultural burns). A 2011 inventory found that up to 20% of PM emissions in the U.S. could be attributed to wildfires alone.

Research assumes that all PM (natural and man-made) affects human health equally. The question of how detrimental smoke from wildfires is to human health is, therefore, a difficult one to answer.

To shed some light on the problem, researchers first need to establish who has been exposed to smoke from natural fires. Usually, they rely on site (ground) measurements and satellite data, but these aren’t always reliable. For instance, site monitors are few and far between in the western US; while satellite data doesn’t provide surface-level concentrations on its own.

To overcome these challenges, the authors of the Atmospheric Chemistry and Physics paper, used Facebook data to determine population-level exposure.

Fires during the summer of 2015 in Canada, as well as Idaho, Washington and Oregon, caused poor air quality conditions in the U.S Midwest. The generated smoke plume was obvious in satellite images. The team used this period as a case study to test their idea.

Facebook was mined for posts which contained the words ‘smoke’,’smoky’, ‘smokey’, ‘haze’, ‘hazey’ or ‘air quality’. The results were then plotted onto a map. To ensure the study was balanced, multiple posts by a single person and those which referenced cigarette smoke or smoke not related to natural causes were filtered out. In addition, towns with small populations were weighted so that those with higher populations didn’t skew the results.

The social media results were then compared to smoke measurements acquired by more traditional means: ground station and satellite data.

Example datasets from 29 June 2015. (a) Population – weighted, (b) average surface concentrations of particulate matter, (c) gridded HMS smoke product – satellite data, (d) gridded, unfiltered MODIS Aqua and MODIS Terra satellite data (white signifies no vaild observation), and (e) computer simulated average surface particulate matter. Image and caption (modified) from B.Ford et al., 2017.

The smoke plume ‘mapped out’ by the Facebook results correlates well with the plume observed by the satellites. The ‘Facebook plume’ doesn’t extend as far south (into Arkansas and Missouri) as the plume seen in the satellite image, but neither does the plume mapped out by the ground-level data.

Satellites will detect smoke plumes even when they have lifted off the surface and into the atmosphere. The absence of poor air quality measurements in the ground and Facebook data, likely indicates that the smoke plume had lifted by the time it reached Arkansas and Missouri.

The finding highlights, not only that the Facebook data can give meaningful information about the extend and location of smoke plume caused by wildfires, but that is has potential to more accurately reveal the air quality at the Earth’s surface than satellite data.

The relationship between the Facebook data and the amount of exposure to particular matter is complex and more difficult to establish. More research into how the two are linked will mean the researchers can quantify the health response associated with wildfire smoke. The findings will be useful for policy and decision-makers when it comes to limiting exposure in the future and have the added bonus of providing a cheap way to improve the predictions, without having to invest in expanding the ground monitor network.

By Laura Roberts, EGU Communications Officer

References

Ford, B., Burke, M., Lassman, W., Pfister, G., and Pierce, J. R.: Status update: is smoke on your mind? Using social media to assess smoke exposure, Atmos. Chem. Phys., 17, 7541-7554, https://doi.org/10.5194/acp-17-7541-2017, 2017.

June GeoRoundUp: the best of the Earth sciences from around the web

June GeoRoundUp: the best of the Earth sciences from around the web

Drawing inspiration from popular stories on our social media channels, as well as unique and quirky research news, this monthly column aims to bring you the best of the Earth and planetary sciences from around the web.

Major Story

With June being the month when the world’s oceans are celebrated with World Ocean Day (8th June) and the month when the UN’s Ocean Conference took place, it seemed apt to dedicate our major story to this precious, diverse and remote landscape.

In fact, so remote and inaccessible are vast swathes of our oceans, that 95% of them are unseen (or unvisited) by human eyes. Despite their inaccessibility, humans are hugely reliant on the oceans.  According to The World Bank, the livelihoods of approximately 10 to 12% of the global population depends on healthy oceans and more than 90%of those employed by capture fisheries are working in small-scale operations in developing countries. Not only that, but the oceans trap vast amounts of heat from the atmosphere, limiting global temperature rise.

Yet we take this valuable and beautiful resource for granted.

As greenhouse gas emissions rise, the oceans must absorb more and more heat. The ocean is warmer today than it has been since recordkeeping began in 1880. Over the past two decades this has resulted in a significant change in the composition of the upper layer of water in our oceans. Research published this month confirms that ocean temperatures are rising at an alarming rate, with dire consequences.

Corals are highly sensitive to changes in ocean temperatures. The 2015 to 2016 El Niño was particularly powerful. As its effects faded, ocean temperatures in the Pacific, Atlantic and Indian oceans remained high, meaning 70 percent of corals were exposed to conditions that can cause bleaching. Almost all of the 29 coral reefs on the U.N. World Heritage list have now been damaged by bleaching.

This month, the National Oceanic and Atmospheric Administration (NOAA) declared that bleaching was subsiding for the first time in three years. Some of the affected corals are expected to take 10 to 15 years to recover, in stress-free conditions. But as global and ocean temperatures continue to rise, corals are being pushed closer to their limits.

Warmer ocean temperatures are also causing fish to travel to cooler waters, affecting the livelihoods of fishermen who depend on their daily catch to keep families afloat and changing marine ecosystems forever. And early this month, millions of sea-pickles – a mysterious warm water loving sea creature- washed up along the western coast of the U.S, from Oregon to Alaska. Though scientists aren’t quite sure what caused the bloom, speculation is focused on warming water temperatures.

It is not only warming waters which are threatening the world’s oceans. Our thirst for convenience means a million plastic bottles are bought around the world every minute. Campaigners believe that the environmental crisis brought about by the demand for disposable plastic products will soon rival climate change.

In 2015 researchers estimated that 5-13 million tonnes of plastics flow into the world’s oceans annually, much coming from developing Asian nations where waste management practices are poor and the culture for recycling is limited. To tackle the problem, China, Thailand, Indonesia and the Philippines vouched to try and keep more plastics out of ocean waters. And, with a plastic bottle taking up to 450 years to break down completely, what happens to it if you drop it in the ocean? Some of it, will likely find it’s way to the Arctic. Indeed, recent research suggests that there are roughly 300 billion pieces of floating plastic in the polar ocean alone.

A bottle dropped in the water off the coast of China is likely be carried eastward by the north Pacific gyre and end up a few hundred miles off the coast of the US. Photograph: Graphic. Credit: If you drop plastic in the ocean, where does it end up? The Guardian. Original Source: Plastic Adrift by oceanographer Erik van Sebille. Click to run.

And it’s not only the ocean waters that are feeling the heat. As the demand for resources increases, the need to find them does too. The sea floor is a treasure trove of mineral and geological resources, but deep-sea mining is not without environmental concerns. Despite the ethical unease, nations are rushing to buy up swathes of the ocean floor to ensure their right to mine them in the future. But to realise these deep-water mining dreams, advanced technological solutions are needed, such as the remote-controlled robots Nautilus Minerals will use to exploit the Bismarck Sea, off the coast of Papua New Guinea.

What you might have missed

Lightning reportedly ignited a deadly wildfire in Portugal, seen here by ESA’s Proba-V satellite on 18 June.

“On June 17, 2017, lightning reportedly ignited a deadly wildfire that spread across the mountainous areas of Pedrógão Grande—a municipality in central Portugal located about 160 kilometers (100 miles) northeast of Lisbon”, reported NASA – National Aeronautics and Space Administration. The death toll stands at 62 people (as reported by BBC News). The fires were seen from space by satellites of both NASA and ESA – European Space Agency satellites.

Large wildfires are also becoming increasing common and severe in boreal forests around the world. Natural-color images captured by NASA satellites on June 23rd, shows wildfires raging near Lake Baikal and the Angara River in Siberia. At the same time, a new study has found a link between lightning storms and boreal wildfires, with lightning strikes thought to be behind massive fire years in Alaska and northern Canada. This infographic further explores the link between wildfires triggered both by lightning and human activities.

Meanwhile, in the world’s southernmost continent the crack on the Larsen C ice-shelf continues its inexorable journey across the ice. The rift is set to create on of the largest iceberg ever recorded. Now plunged in the darkness of the Antarctic winter, obtaining images of the crack’s progress is becoming a little tricker. NASA used the Thermal Infrared Sensor (TIRS) on Landsat 8 to capture a false-color image of the crack. The new data, which shows an acceleration of the speed at which the crack is advancing, has lead scientists to believe that calving of the iceberg to the Weddell Sea is imminent.

Links we liked

The EGU story

This month saw the launch of two new division blogs over on the EGU Blogs: The Solar-Terrestrial Sciences and the Geodynamics Division Blogs. The EGU scientific divisions blogs share division-specific news, events, and activities, as well as updates on the latest research in their field.

And don’t forget! To stay abreast of all the EGU’s events and activities, from highlighting papers published in our open access journals to providing news relating to EGU’s scientific divisions and meetings, including the General Assembly, subscribe to receive our monthly newsletter.

Imaggeo on Mondays: Fire Watch Constellation

Imaggeo on Mondays: Fire Watch Constellation

Wild fires: raging walls of flames, capable of burning down swathes of pristine, sometimes protected and ancient, landscapes have been causing havoc around the globe. Managing and controlling them is no easy task; they can unexpectedly change their course with the wind and jump across rivers, roads and man-made fire breaks.

The significant threat they pose, and damage they can cause, to valuable ecosystems worldwide has been recently evidenced by the destruction of 180 million year old forests in Tasmanian; so unique they are a designated United Nations World Heritage wilderness land. Not only that, wildfires can have sever effects on air quality, directly impacting human health, while at the same time contributing hefty amounts of greenhouse gases to the atmosphere. As recently as the end of last year (2015), forest fires in Indonesia were hailed as a ‘crime against humanity‘, after causing over 500,000 cases of acute respiratory tract infections.

This week’s Imaggeo on Mondays photograph highlights an emerging field of research where scientists are developing new methods to try and better understand the past impact of wildfires and how they contributed (or not) to climate change.

Of his image, Egle Rackauskaite writes: This composite shows a constellation of combined visual and infrared imaging of a smouldering combustion front spreading radially over a thin sample of dry peat. The central watch is created by a series of twelve wedges. Each wedge is extracted from a photo taken every 5 min from an elevated view looking down into the sample during the one-hour lab experiment. The circular peat sample (D=22 cm) was ignited on the centre by an electrical heater. The average radial spread rate was 10 cm/h and the peak temperature 600°C. The top figures show the virgin peat (left) and the final residue (right). The bottom figures show the wedges in visual (left) and infrared (right) imaging. Smouldering combustion is the driving phenomenon of wildfires in peatlands, like those causing haze episodes in southeast Asia and Northeast Europe. These are the largest fires on Earth and an extensive source of greenhouse gases, but poorly studied. Our experiments help to understand this emerging research topic in climate-change mitigation by characterizing the dynamics of ignition, spread and extinction, and also measure the yield of carbon emissions.

If you pre-register for the 2016 General Assembly (Vienna, 17 – 22 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

 

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