King Tides Show Us How Climate Change Will Threaten Coastal Cities

(playful music)

[Voiceover] Climate change is coming and with

it rising sea levels that are

threatening coastal cities like San Francisco.

It's hard to imagine what a few feet of extra

water sloshing around will mean.

But King tides, the highest tides of the year,

give us a glimpse of the soon

to be new normal.

So the King tides are the highest high tides

of the year and as you can see here, when

we have a very high tide it actually overtops a

lot of our infrastructure in San Francisco, in

Marin county, all along the shoreline of

the San Francisco bay.

These tides are a way for us to visualize what

the future of sea level rise will be like.

King tides are caused by an alignment of the

sun and the moon.

When the sun and the moon and the Earth are all

in alignment the gravitational pull is

higher on those tides.

Well right now what we have is the King tides that

happen every year, they're a little higher than what

we get for normal high tides.

We have an El Nino affect which involves warming

of water which makes the water a higher elevation as well.

And then a bit of a low pressure zone with the

rain falling and that allows expansion of

the water even still further.

As we see the water sloshing over behind us that's

what we are going to see every single day,

2030, 2040, 2050, depending on how climate

change and sea level rise go.

When you add the King tide and the El Nino and

the storm surge effects together, we can start to

see the kind of sea level rise, or the kind of

sea levels that we are gonna see on a

permanent basis by the end of the century.

We might see five or six feet of sea level rise and

that's water up at about this level.

[Voiceover] When the sea level does rise,

it's going to swallow more than some sidewalk.

Both San Francisco's and Oakland's

airports are in the flood zone.

So are the headquarters for Google, Facebook, and

hundreds of other tech companies.

And of course, California isn't the only place

threatened by rising sea levels.

Practically anywhere with a shoreline is at risk.

Engineers are working on ways to protect homes,

businesses, and infrastructure.

But with about 40% of the US population living

in coastal communities, they have

their work cut out for them.

Want to get a glimpse of the future?

Head to the shore nearest you on

January 21st or 22nd.