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  • Istanbul straddles a strait between Europe and Asia.

  • Time and time again, it's shaken by unpredictable, strong earthquakes.

  • Istanbul is extremely at-risk.

  • Over the past fifty years, this megacity has grown from

  • a population of about one Million residents to fifteen Million.

  • It's a race against the clock,

  • posing a challenge to disaster management teams,

  • and local residents.

  • The city lacks buildings that can withstand quakes.

  • 95 percent of all houses would have to be demolished.

  • We face a terrible situation.

  • It's not just the quake itself, it's the aftermath too.

  • Is it possible to predict the next big earthquake?

  • Seismologists are developing a new method.

  • The best-case scenario would be to put out a sort offever curve,”

  • where every day we could estimate if there's a higher

  • or lower risk of an earthquake.

  • But forecasting too far in advance has risks of its own.

  • People would storm the banks. They would storm the stores.

  • They would turn on each other.

  • Are there security forces or a plan in place for this type of scenario?

  • No!

  • The countdown for seismologists and emergency responders is on.

  • More than 15 Million people live in this coastal city.

  • And it is becoming increasingly crowded.

  • The Bosporus Strait divides Istanbul into a European and an Asian side.

  • The region is particularly prone to earthquakes.

  • In 1999, less than one hundred kilometers from the city center,

  • an earthquake strikes.

  • It's one of the worst in Turkey's history.

  • At least 18,000 people die.

  • Hundreds of thousands are left homeless.

  • Emergency responders are often too late.

  • There is no working emergency plan or early warning system in place.

  • Thousands of buildings collapse like houses of cards.

  • Sandy subsoil and shoddy construction are to blame.

  • Seismologists expect

  • a similarly powerful earthquake in the coming years,

  • this time right off the coast of Istanbul.

  • A good 1700 kilometers away:

  • At the German Research Centre for Geosciences in Potsdam,

  • scientists monitor earthquakes all over the world.

  • Seismologist Marco Bohnhoff and his team

  • are studying the city on the Bosporus.

  • The earth's crust is especially unstable in the region.

  • Istanbul is extremely at-risk.

  • Over the past fifty years, this megacity has grown from

  • a population of about one Million residents

  • to more than fifteen Million.

  • And unfortunately, just off the coast of Istanbul,

  • there's an active plate boundary and from what we can tell,

  • it's under enormous stress.

  • A tremendous amount of energy is currently building up underground.

  • Like all continents, Europe sits atop tectonic plates.

  • Directly in front of Istanbul in the Sea of Marmara, the Eurasian plate

  • meets the Anatolian plate, forming a so-called fault zone.

  • Typically, these plates push past each other bit by bit.

  • And gas bubbles rise from the ocean floor.

  • We can see this from footage taken

  • by a French-German-Turkish research team.

  • But right off the coast of Istanbul, the plates are stuck.

  • We don't see the usual gas bubbles.

  • At spots where the earth's plates cannot move alongside each other,

  • the pressure builds.

  • Energy accumulates.

  • If it discharges, the plates could move forward

  • by up to 5 meters at once...

  • ...triggering a violent earthquake...

  • ...right in front of the coastal city.

  • The government forecasts 30,000 to 80,000 deaths could result.

  • Experts even say a tsunami is likely, with waves as high as four meters.

  • Seismologists predict the earthquake will have a magnitude of at least 7.

  • Earthquakes are measured on a scale of 1 to 9.5.

  • Quakes with a magnitude of 4 are felt by most people in the area.

  • A magnitude 7 quake is considered particularly strong.

  • Bohnhoff's team wants to use a new method

  • to predict powerful earthquakes like these in the future.

  • There is a series of indicators we can observe

  • before an earthquake strikes.

  • And if we can systematically record and evaluate them

  • automatically in real time,

  • it would be essentially be possible to look at the fever curve

  • of a fault zone 24 hours a day.

  • And then issue warnings when necessary.

  • That would be revolutionary.

  • So far, early warning systems around the world react - at most

  • a few seconds beforehand.

  • So-calledseismographs

  • register the less powerful primary waves of an earthquake,

  • sending a signal just seconds before the destructive secondary waves start.

  • Mexico City uses such a system.

  • In 2017, there were two particularly strong quakes here.

  • About 20 seconds beforehand, residents were warned

  • via public loudspeakers, saving thousands of lives.

  • This was possible because the epicenter of the quake

  • was far outside the city.

  • In 2011,

  • Tokyo experienced one of the most severe

  • earthquakes ever seen worldwide.

  • The city's residents were warned via television, radio and the Internet

  • nearly 80 seconds beforehand.

  • In those precious seconds, the city can shut off gas lines,

  • switch traffic lights to red and bring trains to a halt.

  • Istanbul also has an early warning system.

  • But it's only for the disaster management team.

  • And the warning period is limited to just 5 seconds.

  • At the Disaster Coordination Center,

  • that is not enough time to warn residents.

  • Because that time span is so short,

  • people would not be able to escape in the event of a quake.

  • That's why our system is limited to preventing accidents or fires,

  • for example by automatically turning off the gas.

  • Employees of local transportation and gas utility as well as firefighters

  • are often on standby in case of an earthquake.

  • They also get some help from the computer software, ELER.

  • Depending on the magnitude and location of the quake,

  • the program immediately calculates the number of potential deaths

  • or collapsed buildings.

  • Then we have to compare the computer's estimation

  • with what's actually going on.

  • To do this, we use information from the team that's onsite,

  • for example, the fire department.

  • Then we can be confident we're sending the right team to the right place.

  • Residents must also be prepared.

  • At the Disaster Training Center in Kozyatağı,

  • an eighth-grade class is running through drills today.

  • So how close is the danger?

  • This is the North Anatolian Fault Zone...

  • We are only 12 kilometers away from it here in this district.

  • That means a quake would be felt especially strongly here.

  • A simulator generates a quake with a magnitude of 6.7.

  • The children only have a few seconds to duck under the table.

  • It's important they remember to protect their heads.

  • When the quake is over, the students can run outside

  • but not before turning off gas

  • and electrical appliances to prevent fires.

  • I only knew a little about earthquakes before this.

  • But now I've experienced it and understand what to do.

  • The instructor, Cenk Tankal,

  • recommends always having an emergency backpack ready to go:

  • Equipped with water, a flashlight and a first aid kit.

  • Professional aid won't come for the first 72 hours of a disaster.

  • Therefore, we must be prepared for survival until help arrives.

  • But these tips are only useful if buildings and infrastructure

  • can withstand the earthquakes.

  • On the European side of the city, a subway line is being extended.

  • Civil engineer Mustafa Murteza

  • is supervising the project on behalf of the municipality.

  • In the district of Kağıthane,

  • the tracks emerge above ground and cross a bridge.

  • It is supposed to be safe for an earthquake up to a magnitude of 7.5.

  • But the soil poses a risk.

  • We have to cover a long distance here,

  • but the ground is very muddy and unstable.

  • This is dangerous during quakes.

  • That's why we dug very deep into the earth

  • to connect the bridge's pillars with stable ground.

  • A 70-meter-long steel structure will anchor the bridge to firmer ground.

  • The subway control center:

  • This is where emergency plans should take effect in the event of a quake:

  • stop elevators,

  • switch escalators to move up only,

  • slow down and evacuate trains.

  • And then, while we're filming, this happens

  • A moderate earthquake with a magnitude of 5.8 hits the city.

  • It is the second earthquake within a matter of days.

  • There hasn't been a situation like this for many years.

  • I was at work.

  • At first, I thought something struck my chair, then it started shaking.

  • We were evacuated immediately. Now I'm here to pick up my child.

  • Good luck!

  • Cell phone service is disrupted.

  • Those who can, try to reach their friends and family.

  • The houses here are all old, so we are very afraid.

  • I can't reach my family, the lines are down.

  • I am also afraid to go home.

  • I am nervous, very nervous.

  • I can't even picture what the big quake would be like.

  • Fortunately, there are no deaths or injuries.

  • But many buildings, including this minaret, are damaged.

  • One day later.

  • Tayfun Kahraman

  • is the head of earthquake risk management for the city.

  • He's faced with a big challenge.

  • The city's warning system did not activate during the quake.

  • You can't say the system worked as it should have.

  • We have 10 stations at the moment

  • but we aren't receiving a signal from any of them, not even yesterday.

  • Our task now is to build more stations

  • and repair the 10 we already have.

  • Turkey's conservative party ruled Istanbul for 25 years

  • until the summer of 2019.

  • Kahraman says the party did not do enough

  • to prepare the city for earthquakes.

  • Unfortunately,

  • we cannot say that Istanbul is prepared for an earthquake today.

  • There are still buildings here that are in danger of collapsing.

  • After all, even the 5.8 magnitude quake caused major damage.

  • The new city government wants to set new priorities.

  • Today, Kahraman hosts representatives

  • from the MAG-DER foundation at City Hall.

  • For about two decades, this group of scientists, merchants and craftsmen

  • have been trying to prepare Istanbul residents for the next big earthquake.

  • Traumatized by the 1999 quake,

  • they do not want to leave their fate in the hands of the state alone.

  • Our mission is that within the first 72 hours after a quake,

  • everyone is active in their own neighborhood.

  • We want to train 4 to 5 volunteers in each district

  • to form a civilian disaster rescue team.

  • The new city administration wants to work together with the foundation.

  • For disaster management expert Özden Işık, this is a ray of hope.

  • We have come to the right place.

  • He will support our projects,

  • develop them further and he also has plans of his own.

  • The earthquake was a wakeup call for the whole city.

  • At a panel discussion, the foundation MAG-DER

  • informs residents about the dangers of earthquakes.

  • There's quite a bit of interest.

  • Özden Işık tells them what they must avoid at all costs, is panic.

  • When combating a disaster, the most important asset we have is people.

  • But only if those people are prepared and can act reflexively.

  • If they are not prepared,

  • then they become a liability because they panic.

  • Back in Potsdam, Germany.

  • During laboratory tests,

  • seismologist Marco Bohnhoff has a breakthrough.

  • He uses various types of stone to simulate earthquakes.

  • In the real world, there might be 100 or 200 years

  • between two strong quakes.

  • We do not have that time.

  • So instead, we simulate these processes at an accelerated rate.

  • We increase the pressure relatively quickly

  • and then retrieve the measured values so we can do our calculations.

  • Ultimately, we can recreate a complete cycle from one quake

  • to the next within a few minutes.

  • Bohnhoff tests it out with a sandstone sample.

  • A press applies an enormous amount of pressure to the stone.

  • The machine simultaneously registers acoustic signals

  • that reveal what is happening to the stone internally.

  • Slowly, the machine increases the pressure on the stone.

  • It's as if 30 trucks were stacked up on one finger.

  • On the surface, it appears the stone hasn't changed.

  • But the acoustic signals on the monitor show another story:

  • It's beginning to fracture.

  • More and more cracks become visible - like small, miniature quakes.

  • Fifteen minutes later, the stone breaks.

  • Marco Bohnhoff says the same logic

  • can be applied to large-scale earthquakes.

  • We're seeing all of this foreshock activity before the point of fracture.

  • And since that's similar for all rock samples,

  • we are hopeful we can apply this method.