Summary Reader Response Draft #3 Final

In the article “How Volcanic Ash Strengthens A Roof Against Powerful Projectiles”, Williams (2019) states that the addition of volcanic ash layers on the roofs can mitigate the impact of volcanic projectiles on shelters around active volcanoes.

Williams claims that scientists had discovered mountain huts were capable of providing life-saving shelter for hikers during the eruption that took place at Mount Ontake, Japan 2014. This finding inspired the scientists to further study on how the addition of volcanic ash on roofs could reduce impacts of projectiles. Through meticulous simulation, scientists were able to deduce that the thickness of ash deposit is proportional to the roofs’ energy absorption rate from projectiles. Five centimeters of ash layer tripled the strength of the roof from projectiles. However, heavier loads of ash may affect the structural integrity of the roof.

Additionally, he states that scientists expected buildings to take more damage from multiple volcanic hazards as compared to one. Tests proved otherwise, on condition that tephra is placed on roofs before impacts. Williams concludes that researchers will conduct further investigation to determine the optimum range of ash deposit layers to achieve a balance between reducing impact of projectiles and risk of roof collapsing. While the article does focus on using volcanic ash to shield the roof of buildings nearby volcanic areas from volcanic projectiles, it lacks the information on other hazards of a volcanic eruption that pose a bigger threat not only to buildings but humans as well.

More importantly, there are negative impacts of using volcanic ash on roofs that readers should know beforehand. Maintenance for using volcanic ash is high and personal protective gear must be used when handling it. Due to ash being on the roofs, it is exposed to wind and rain. Ash may be blown away towards drainage pipes and corrode or block the water flow, leading to poor water hygiene (USGS, 2015). “When ash is wet , static loads may increase by up to hundred percent.” (USGS, 2015), which will cause a roof to collapse.

A hazard that pose a bigger threat is called pyroclastic density current(PDC). Majority of fatalities from volcanic hazards comes from PDC (Brown et al., 2017). PDC contains a mixture of volcanic gas, ash and rock fragments. These rock fragments can be as large as boulders that travel at a very high velocity destroying majority of structures in their trail, to the extend where reinforcement rods in concrete can crook towards the flow of PDC (USGS, 2016). Linking back to the simulation done by Williams and the scientists, launching volcanic rocks, the size of large boulders, to accurately test the impact on structures was sceptical. The launching and projectile speed had to be on par with a volcanic eruption speed. In addition, the simulation did not specify what volcanic rock sizes were used for the experiment thus readers may find the results to not be credible.

Another hazard is volcanic gases. Substantial amounts of sulfur dioxide, carbon dioxide, hydrogen sulfide can be released from volcanoes and high doses of these gases are harmful to the human body (USGS, 2017).  In 1986, high amounts of carbon dioxide were released from Lake Nyos and killed about 1700 people (Nasr, 2009). Sulfur dioxide and hydrogen sulfide are similar whereby they affect our respiratory system and prolong high exposure to humans will result in death (USGS, 2017). These gases are not be taken lightly and measures to mitigate exposure should be included in the article for education purposes.

Overall, Williams could cover more content on the other volcanic hazards. He should also take in account for the difficulties of using volcanic ash on roofs as the disadvantages easily outweigh the advantages.

References

Brown, S.K., Jenkins, S.F., Sparks, Sparks, R.S.J., Odbert, H., Auker, M.R. (2017).  Volcanic fatalities database: analysis of volcanic threat with distance and victim classification. Journal of Applied Volcanology. https://doi.org/10.1186/s13617-017-0067-4

Nasr, S.L. (2009, March 24) How did Lake Nyos suddenly kill 1,700 people? . Retrieved from https://science.howstuffworks.com/environmental/earth/geophysics/lake-nyos.htm

U.S. Geological Survey. (2016, February 12).  Pyroclastic flows move fast and destroy everything in their path. https://volcanoes.usgs.gov/vhp/pyroclastic_flows.html

U.S. Geological Survey. (2017, May 10). Volcanic gases can be harmful to health, vegetation and infrastructure. https://volcanoes.usgs.gov/vhp/gas.html

U.S. Geological Survey. (2015, December 17). Volcanic Ash Impacts & Mitigation: Buildings. https://volcanoes.usgs.gov/volcanic_ash/buildings.html

Williams,G.T. (2019, November 12). How Volcanic Ash Strengthens A Roof Against Powerful Projectiles. Earth Observatory Blog. Retrieved from https://www.earthobservatory.sg/blog/how-volcanic-ash-strengthens-roof-against-powerful-projectiles

Summary Reader Response Draft #2

In the article “How Volcanic Ash Strengthens A Roof Against Powerful Projectiles”, Williams (2019) states that the addition of volcanic ash layers on the roofs can mitigate the impact of volcanic projectiles on shelters around active volcanoes.

Williams claims that scientists had discovered mountain huts were capable of providing life-saving shelter for hikers during the eruption that took place at Mount Ontake, Japan 2014. This finding inspired the scientists to further study on how the addition of volcanic ash on roofs could reduce impacts of projectiles. Through meticulous simulation, scientists were able to deduce that the thickness of ash deposit is proportional to the roofs’ energy absorption rate from projectiles. Five centimeters of ash layer tripled the strength of the roof from projectiles. However, heavier loads of ash may affect the structural integrity of the roof.

Additionally, he states that scientists expected buildings to take more damage from multiple volcanic hazards as compared to one. Tests proved otherwise, on condition that tephra is placed on roofs before impacts. Willams concludes that researchers will conduct further investigation to determine the optimum range of ash deposit layers to achieve a balance between reducing impact of projectiles and risk of roof collapsing. While the article does focus on using volcanic ash to shield the roof of buildings nearby volcanic areas from volcanic projectiles, it lacks the information on other hazards of a volcanic eruption that poses a bigger threat not only to buildings but humans as well.

Majority of fatalities from volcanic hazards comes from a hazard called pyroclastic density current (PDC) (Brown et al., 2017). PDC contains a mixture of volcanic gas, ash and rock fragments. These rock fragments can be as large as boulders that travel at a very high velocity destroying majority of structures in their trail, to the extend where reinforcement rods in concrete can crook towards the flow of PDC (USGS, 2016). In my opinion, linking back to the simulation done by Williams and the scientists, I believed that they could not have launched volcanic rocks, the size of large boulders, to accurately test the impact on structures. The launching and projectile speed had to be on par with a volcanic eruption speed. In addition, the simulation did not specify what volcanic rock sizes were used for the experiment thus readers may find the results to not be credible.

To add on, a hazard that poses a big threat to humans are volcanic gases. Substantial amounts of sulfur dioxide, carbon dioxide, hydrogen sulfide can be released from volcanoes and high doses of these gases are harmful to the human body (USGS, 2017).  In 1986, high amounts of carbon dioxide were released from Lake Nyos and killed about 1700 people (Nasr, 2009). Sulfur dioxide and hydrogen sulfide are similar whereby they affect our respiratory system and prolong high exposure to humans will result in death (USGS, 2017). These gases should not be taken lightly, and measures should be included in the article for education purposes.

More importantly, there are negative impacts of using volcanic ash on roofs that were not emphasized. Maintenance for using volcanic ash is high and personal protective gear must be used when handling it. Due to ash being on the roofs, it is exposed to wind and rain. Ash may be blown away towards drainage pipes and corrode or block the water flow, leading to poor water hygiene (USGS, 2015). “When ash is wet , static loads may increase by up to hundred percent.” (USGS, 2015), which will cause a roof to collapse.

Overall, Williams could cover more content on the other volcanic hazards. I feel the disadvantages of using volcanic ash on buildings outweighs the positive impacts stated in the article.

References

Nasr, S.L. (2009, March 24) How did Lake Nyos suddenly kill 1,700 people? . Retrieved from https://science.howstuffworks.com/environmental/earth/geophysics/lake-nyos.htm

Williams,G.T. (2019, November 12). How Volcanic Ash Strengthens A Roof Against Powerful Projectiles. Earth Observatory Blog.

Retrieved from https://www.earthobservatory.sg/blog/how-volcanic-ash-strengthens-roof-against-powerful-projectiles

Brown, S.K., Jenkins, S.F., Sparks, Sparks, R.S.J., Odbert, H., Auker, M.R. (2017).  Volcanic fatalities database: analysis of volcanic threat with distance and victim classification. Journal of Applied Volcanology. https://doi.org/10.1186/s13617-017-0067-4

U.S. Geological Survey. (2016, February 12).  Pyroclastic flows move fast and destroy everything in their path. https://volcanoes.usgs.gov/vhp/pyroclastic_flows.html

U.S. Geological Survey. (2017, May 10). Volcanic gases can be harmful to health, vegetation and infrastructure. https://volcanoes.usgs.gov/vhp/gas.html

U.S. Geological Survey. (2015, December 17). Volcanic Ash Impacts & Mitigation: Buildings. https://volcanoes.usgs.gov/volcanic_ash/buildings.html

Summary Reader Response Draft #1

In the article “How Volcanic Ash Strengthens A Roof Against Powerful Projectiles”, Williams (2019) states that the addition of volcanic ash layers on the roofs can mitigate the impact of volcanic projectiles on shelters around active volcanoes.

Williams claims that scientists had discovered mountain huts were capable of providing life-saving shelter for hikers during the eruption that took place at Mount Ontake, Japan 2014. This finding inspired the scientists to further study on how the addition of volcanic ash on roofs could reduce impacts of projectiles. Through meticulous simulation, scientists were able to deduce that the thickness of ash deposit is proportional to the roofs’ energy absorption rate from projectiles. Five centimeters of ash layer tripled the strength of the roof from projectiles. However, heavier loads of ash may affect the structural integrity of the roof.

Additionally, he states that scientists expected buildings to take more damage from multiple volcanic hazards as compared to one. Tests proved otherwise, on condition that tephra is placed on roofs before impacts. Willams concludes that researchers will conduct further investigation to determine the optimum range of ash deposit layers to achieve a balance between reducing impact of projectiles and risk of roof collapsing. While the article does focus on using volcanic ash to shield the roof of buildings nearby volcanic areas from volcanic projectiles, it lacks the information on other hazards of a volcanic eruption that poses a bigger threat not only to buildings but humans as well.

Majority of fatalities from volcanic hazards comes from a hazard called pyroclastic density current (PDC) (Brown et al., 2017). PDC contains a mixture of volcanic gas, ash and rock fragments. These rock fragments can be as large as boulders that travel at a very high velocity destroying majority of structures in their trail. To the extend where reinforcement rods in concrete can crook towards the flow of PDC (USGS, 2016). In my opinion, linking back to the simulation done by Williams and the scientists, I believed that they could not have launched volcanic rocks, the size of large boulders, to test the impact on structures. The launching and projectile speed had to be on par with a volcanic eruption speed. In addition, the simulation did not specify what volcanic rock sizes were used for the experiment thus readers may find the results to not be credible.

To add on, a hazard that poses a big threat to humans are volcanic gases. Substantial amounts of sulfur dioxide, carbon dioxide, hydrogen sulfide can be released from volcanoes and high doses of these gases are harmful to the human body (USGS, 2017).  In 1986, high amounts of carbon dioxide were released from Lake Nyos and killed about 1700 people (Nasr, 2009). Sulfur dioxide and hydrogen sulfide are similar whereby they affect our respiratory system and prolong high exposure to humans will result in death. These gases should not be taken lightly, and measures should be included in the article for education purposes.

More importantly, there are negative impacts of using volcanic ash on roofs that were not emphasized. I feel the cons of using volcanic ash on buildings outweighs the positive impacts stated in the article. Due to ash being on the roofs, it is exposed to wind and rain. Ash may be blown away towards drainage pipes and corrode or block the water flow, leading to poor water hygiene. “When ash is wet , static loads may increase by up to hundred percent.” (USGS, 2015), which will cause a roof to collapse. Overall, maintenance is high and personal protective gear must be used when handling volcanic ash.

References

Nasr, S.L. (2009, March 24) How did Lake Nyos suddenly kill 1,700 people? . Retrieved from https://science.howstuffworks.com/environmental/earth/geophysics/lake-nyos.htm

Williams,G.T. (2019, November 12). How Volcanic Ash Strengthens A Roof Against Powerful Projectiles. Earth Observatory Blog.

Retrieved from https://www.earthobservatory.sg/blog/how-volcanic-ash-strengthens-roof-against-powerful-projectiles

Brown, S.K., Jenkins, S.F., Sparks, Sparks, R.S.J., Odbert, H., Auker, M.R. (2017).  Volcanic fatalities database: analysis of volcanic threat with distance and victim classification. Journal of Applied Volcanology. https://doi.org/10.1186/s13617-017-0067-4

U.S. Geological Survey. (2016, February 12).  Pyroclastic flows move fast and destroy everything in their path. https://volcanoes.usgs.gov/vhp/pyroclastic_flows.html

U.S. Geological Survey. (2017, May 10). Volcanic gases can be harmful to health, vegetation and infrastructure. https://volcanoes.usgs.gov/vhp/gas.html

U.S. Geological Survey. (2015, December 17). Volcanic Ash Impacts & Mitigation: Buildings. https://volcanoes.usgs.gov/volcanic_ash/buildings.html

Summary draft #2

In the article “How Volcanic Ash Strengthens A Roof Against Powerful Projectiles”, Williams (2019) states that the addition of volcanic ash layers on the roofs can mitigate the impact of volcanic projectiles on shelters around active volcanoes.

Williams claims that scientists had discovered mountain huts were capable of providing life-saving shelter for hikers during the eruption that took place at Mount Ontake, Japan 2014. This finding inspired the scientists to further study on how the addition of volcanic ash on roofs could reduce impacts of projectiles. Through meticulous simulation, scientists were able to deduce that the thickness of ash deposit is proportional to the roofs’ energy absorption rate from projectiles. Five centimeters of ash layer tripled the strength of the roof from projectiles. However, heavier loads of ash may affect the structural integrity of the roof.

Additionally, he states that scientists expected buildings to take more damage from multiple volcanic hazards as compared to one. Tests proved otherwise, on condition that tephra is placed on roofs before impacts. Willams concludes that researchers will conduct further investigation to determine the optimum range of ash deposit layers to achieve a balance between reducing impact of projectiles and risk of roof collapsing.

Williams,G.T. (2019, November 12). How Volcanic Ash Strengthens A Roof Against Powerful Projectiles. Earth Observatory Blog.

Retrieved from https://www.earthobservatory.sg/blog/how-volcanic-ash-strengthens-roof-against-powerful-projectiles