Is global warming real?

+0,8°

So, if it is +0,1° on 90% of the surface and +10° over the poles, it is still 1 degree average but

thenBIG PROBLEM

Do we care about +1°?

If it is +1° everywhre, including the poles,

OK

The poles = 10% of earth’s surface

+4 　 to +7° at the North pole in January this year!

So, we don’t care about the global temperatureWhat matters is the increase at the poles

The heat is brought from the equator to the poles by the winds

Why are the poles getting warmer?

The earth is like a giant warm plate

cooled down by a small

and very cold spot

Any additional heat will concentrate at the poles

Grenoble (France) today

It was just 8° colder 2 km of ice!!! but 20,000 years ago…

So,what about if we get plus 4° in the future?

?Plus 1 　 degree is not much?

Where does all this mess come from?• Is it natural?• Hope not, because there would be nothing we can do!

• Or is it due to human being activities?• Most probably, even if some natural effect can overlap

A most probable culprit is CO2 which produces greenhouse effect

• Today, it is 1° per 100 years : 10 times faster!

• In the past, natural warming occurred at 10° per 10,000 years (or 1° per 1,000 years)

The greenhouse effect

Heat is trappedThe earth surface temperature would be -15 °C

without the greenhouse effect

Greenhouse effect = life

Without greenhouse effect

Risk of imbalance

Water vapor = 95%; CO2 = 4%

The earth is a greenhousethe glass is our atmosphere

The earth is in equilibrium

Sun heat

10 kg

Radiations

10 kg

Equilibrium temperature at the surface of the earth

= 15°C

But a peanut can have a large effect!!!The equilibrium is slowly broken

The temperature is rising

Human being effect is peanuts!

Carbon dioxide content is rising

We reject 35 billions tons of CO2per year

1 ppm =0,0001 %; 1% = 10,000 ppm

380 ppm is not much?

Still want to take a bath?

If you pour half a glass of wine into your bathtub…

That’s 380 ppm!

Let’s take a bath

We pump carbon from an

underground reservoir

We burn it at the surface to produce

energy

We dump it to the atmospheric

reservoir

Fossil fuel reservoir

almost infinite (if you accept to pay

the price)

Atmospheric reservoir

almost saturated

The problem is not a shortage of oil

But a shortage of air!

Who is polluting our greenhouse?

Road = 1/5th of total (cars = 10%)

Road = ¾ transportationTransportation = 28%

We need green cars• Electric cars represent a good solution– Storage of energy by batteries• Range limited to less than 200 km

• OK if the electricity comes from renewable sources

– Storage of energy by using Hydrogen• More than 600 km range

• H2 can be produced from renewable sources

Electrolysis : one way to produce Hydrogen

Oxydation at the anode

Reduction at the cathode

1,229 V

ELECTROLYSISWater + power H2 + O2

H2 + O2 Power + Water

FUEL CELL

A fuel cell : how does it work?

Hydrogen + Oxygen= electricity + water

1,229 V

H2O

H

Hydrogen fuel cell car

An electrical vehicle without battery•Hydrogen is stored in high pressure tanks (700 atmospheres)•Exhaust : only water vapor

•Can run 500 – 800 km 90-100 mph

X-TRAIL

FCHV

Clarity

Class-A

How to refill the car?

How to produce Hydrogen?

• By water electrolysis : expensive– Electricity from fossil, nuclear or renewable sources

• By cracking natural gas (CH4)– Releases CO2 , but saves 30% compared to burning gasoline

• Or ….

Once　upon　a　time…CO2

biogas

bio-H2

Totally　neutral　and　green

• So, there are plenty ways to reduce our C02 emissions

• Yes indeed, we can limit the global warming

• But will this be enough?

The internet cable network

Apple data center

Data centers in the world = 12 nuclear reactors1 billions PCs = 60 nuclear reactorsModem/routers: 18 nuclear reactors

5% worldwide electricity, rapidly growing

Telephone relay tower