Impact of Tectonics on the Physical Environment. Flashcards
Introduction?
=> Define physical environment. -> E.g morphology, coastal areas.
=> Define volcanoes and earthquakes as tectonics.
=> But also other factors: social, economic, political.
=> Impact is viewed here as scale, influence on other factors, as well as short and long term.
Paragraph 1: Scale?
The greatest impact of tectonic hazards can be on the physical environment due to the scale/ extent of reach that it can have.
Supervolcanoes which are defined as those that have erupted more than 240 cubic miles of material have a global impact on the physical world. -> The eruption of the Toba Caldera led to a volcanic winter with a worldwide decrease in temperature between of up to 15 °C in higher latitudes. -> Much colder planet, impacts climate and physical landscape. Increased risk of extreme events.
ON THE OTHER HAND, tectonic hazards are also shown to have global economic hazards. After the Tonhoku EQ: Companies such as Sony that relied on parts from Japan in overseas supply chains were unable to function as normal, reducing their capability to manufacture as normal. GLOBAL TRADE IMPACTED.
Furthermore, global trade slowed as 40 ports of Japan were shut down, and the stock market lost value as hundreds of companies were forced into bankruptcy in the country, highlighting a national-international impact.
Thus, impacts on physical environment are not the greatest - though both have global reaches, the frequency from economic impacts occurs much more often than supervolcanoes - every 50,000 years.
Paragraph 2: Influence on other factors?
The damage to the physical environment can lead to additional socio-economic and political impacts.
Example: The 250 million stretch coastline during the Tohoku EQ, dropped by 0.6m, allowing the tsunami to travel further inland.
This leads to political impacts -> Damage to the Fukushima nuclear plant, meltdown of generators and release of radioactivity. Led to an unclear future of the nuclear industry, as the government now debates this + fallout with Germany over the anti-nuclear lobby.
Socio-economic: Tsunami brought saline water, which flooded farmland. Not only does the land become uncultivable, it also has economic impacts, losing 3-4% of Japan’s rice production, impacting the livelihoods and work life of farmers in the Tohoku region.
HOWEVER, other factors can also have negative secondary impacts, and this is not just limited to impacts on the physical environment.
For example: Political impacts in Haiti’s 2010 EQ demonstrate the greater importance of governance and stability in the extent of secondary impacts.
Haiti had weak governance beforehand, it did not have a clear disaster response plan, and there was no building protocol. Socio-economic impacts: -> 230,000 killed, 60% of the capital was destroyed.
VS China, who did have a clear plan, where the Sichuan earthquake struck, recovered much more quickly -> 99% of post disaster projects completed by 2012, 4 years later. V A year later in Haiti, only 5% of rubble cleared, despite enormous aid.
Repeated again: 2021 EQ: 2,200 killed, 130,000+ homes destroyed. -> Building codes are often ignored according to UCLBP. No government to help reinforce this, they did not build back better.
VS China, government learnt lesson - Amended laws on mitigating, extensive monitoring from 100,000 new stations. Early warning system spent $2bn Yuan, in 2013 and 2017, minimised damage and saved lives as mechanisms kicked in, preparing the country.
Though both factors are important, other factors like politics are much more important - physicality can be out of control, so focus on what is possible to manage. As shown by China, it focused not on protecting the natural environment, but on reducing social impacts, learning from the Sichuan EQ.. -> 87,000 fatalities. More important to people to reduce this.
Paragraph 3: Impacts of tectonics - short term (positive and negative).
Short term impacts from tectonics can be short term, but also classified as positive or negative for those impacted.
For example: Negative short term impacts from Pinatubo were great as they were physically wide-reaching, impacting both land and air. -> Air saw extensive acid rain due to 22 million tonnes of SO2. -> Land was also vastly damaged by falling ash and pumice, ash was blown over hundreds of kms. Land becomes unusable indefinitely.
HOWEVER, Economic impact: positive impacts via means such as tourism seen with Iceland. -> Eruption led to putting Iceland ‘on the map.’ Tourism earns Iceland $3.5bn dollars, with 5x its population coming in, still short term as E-16 less than 10 years ago.
Thus extent of reach. Regional V International impacts of short term.
Paragraph 4: Long term impacts?
Impacts from volcanic eruptions can lead to -> LIPS as an additional hazard, devastating the physical world. These can change the Earth’s landscape by covering it in lava and volcanic ash. For example: 15 million years ago a LIP created the Columbia River flood-basalts in the N west of the USA.
The long-term vast physical impact cannot be replicated, as it changes the physical environment of the world completely, changing the climate and habitability of the entire planet.
HOWEVER, this is an extraordinarily rare event, happening every 10-20 million years, and has not happened in human lifetime.
Long term impacts that occur via other factors such as socially, have actually impacted people, and so will have a greater impact for us.
Example: Long-term impact on sense of place (social-economic impact) after Sichuan EQ. -> Ruins were preserved as an EQ memorial. There is a mass grave there. It was reframed as a dark tourism location. Commercialisation of ruins V grief of locals, who will never forget the loss of their only child, will haunt them for a lifetime.
Non-physical impacts long-term impact humans more - because these are actually experienced by us.
Conclusion?
Conclusion, ultimately, physical impacts are not the greatest. Whilst the long term impact on the physical environment may be an area in which it outweighs, its placement on the geological time scale is long to be experienced, and thus does not have an impact in practice.
