Volcanic Benefits & Forecasting

Transcription

1 Volcanic Benefits & Forecasting

2 Review:

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4 1. Based on what we know about volcanoes, predict where you might you expect to see volcanoes in and around New Zealand? 2. What type of volcanoes would you expect to find in and around New Zealand?

5 Mt. Ngauruhoe Mt. Egmont

6 Mt. St. Helens what happened? What did your parents experience?

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8 The human population close to active volcanoes is constantly growing, thus volcanic risk is increasing They were born there People are optimistic and believe eruption is unlikely Unaware of the risk They cannot choose where they live (i.e limited by economies) People are fatalistic or risk takers Employment opportunities They land is fertile and good for farming

9 Although volcanoes pose a serious threat to those who live near them, they also provide us with important natural service functions At spreading ridges, magma fills vertical fractures produced and spills out onto the sea floor Active volcanoes produce lava which cools, solidifies, and adds to the earth s surface Habitable islands such as Iceland, Hawaii, the Canary Islands and many other countries would not exist without volcanoes

10 Volcanic eruptions provide lava and pyroclastic deposits, which, when weathered, are excellent for farming Nutrients produced by weathering of volcanic materials allow for crops such as coffee, maize, pineapple, sugar cane, and grapes to thrive How are these soils a double-edged sword?

11 Mount Agung, Bali, Indonesia Mount Sinabung, Indonesia Although volcanic soils provide an important resource, nearby volcanic activity can make it difficult to safely use that resource Soils are attracting employment and communities to the base of the volcanoes

12 Internal heat associated with volcanoes can be used to generate power for nearby urban areas Geothermal power is being generated in Hawaii, California, Nevada, Italy, New Zealand, and Iceland A renewable resource, but still comes with issues Water produced by conversion of steam to power may be acidic or contain high concentrations of heavy metals

13 Natural hot springs attract resorts and health spas Opportunities for hiking, snow sports, & education Tourism 3 million tourists at Yellow Stone National Park per year to see geysers and hot springs 1 million tourists at Kilauea volcano in Hawaii each year Garibaldi provincial parks in BC also a popular tourist attraction Aesthetic value of the natural landscape Recreation opportunities also contribute to local employment in a region

14 Volcanoes are beyond our control, however, we can take action to minimize losses of life and property by forecasting volcanic eruptions 1. Monitoring seismic activity increasing seismic activity a good indicator of an approaching volcanic eruption 2. Monitoring thermal, magnetic, and hydrologic conditions at the volcano increased heat can be detected by satellite sensors, infrared aerial photography or increased snow melt

15 3. Monitoring the land surface to detect tilting or swelling of the volcano Satellite-based radar and GPS satellite receivers to monitor surface changes 4. Monitoring volcanic gas emissions Looking for changes in gas emission rates as well as relative amounts of carbon dioxide and sulphur dioxide 5. Studying the geological history of the volcano Mapping and dating lava flows to study frequency or eruptions

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17 Large amounts of loose or volcanic ash and other pyroclastic material become saturated with water and rapidly move downslope Water can be from severe rain event, rapid melting of snow or ice on volcano Can occur days, week, or years after an eruption Can move 10s of km/hr

18 What are secondary hazards of volcanoes? Due: Monday, April 16 MIND MAP PROJECT ( / 20) Criteria: Minimum five secondary hazards (main themes) Each hazard needs to include branches od further detail. This could be key facts about the hazard, examples of when the hazard has occurred, and/or images & diagrams Mind map should be organized so branches go from more general (main themes) to more specific (detail) Use different colours and/or line types to help distinguish between your main themes Main questing, What are secondary hazards of volcanoes? written in the centre /5 /10 /2 /2 /1 Resource:

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