In the time it took me to walk on stage
around 10 seconds,
more than 10,000 metric tons
of climate-warming gases
have been pumped into the atmosphere
from human actions.
To provide some context
on just how much that is,
That is the weight equivalent
of 170,000 of me
emitted in gas in 10 seconds.
Ninety-nine percent of this pollution
is carbon dioxide, CO2,
and we know we need to reduce it.
The other one percent
is almost entirely methane,
which mostly comes
from producing fossil fuels,
managing waste and raising livestock.
But that one percent of methane
could cause more warming
over the next 10 years than all that CO2.
This is because methane absorbs
a lot more energy per unit mass
for reasons relating to its
molecular structure
and its ability to form other
greenhouse gases in the atmosphere.
CO2 is important because it can
linger in the atmosphere
long after it is emitted,
which means we must achieve
net-zero emissions
to eventually stabilize our climate.
This is key for protecting
generations to come.
But with climate change already
devastating so many lives today,
we can't focus only on the distant future.
My work as a scientist
aims to identify ways
to slow down warming as fast as possible,
so that we can lower the risks
of worsening damages in the near future.
This is where methane comes in.
That one percent of methane
may cause more warming
than all that CO2
in the next several years,
but it only lasts in the atmosphere
for around a decade.
Methane's warming power is therefore
not from the gradual buildup over time
like CO2,
but almost entirely from recent emissions.
This means that every time
we reduce methane,
we can reduce a lot of warming right away.
In fact, cutting methane
is the single fastest,
most effective opportunity to immediately
slow down the rate of warming.
(Applause)
And this is because not only
does methane act fast,
but because we can act fast
because we have the technologies
available right now
to cut methane emissions
from human activities in half.
And even better, many
of these solutions pay for themselves.
The methane we emit
comes from three main sources:
energy production,
waste management and agriculture.
The first category, energy production,
is the largest and cheapest
opportunity we have
to cut methane today.
Most methane from energy
isn't from burning fossil fuels,
it's from producing fossil fuels.
Because natural gas,
which is mostly methane,
can easily escape into the atmosphere
when extracting oil, gas and coal,
or when transporting gas
through pipelines.
In fact, these leaks can completely offset
any near-term climate benefits
of using gas instead of coal.
But we have the technologies
to cut the majority of these emissions
with around half for no net cost
because the saved gas can be sold.
For example, oil fields in West Texas
are wasting enough gas right now
to heat more than two million homes.
Fixing the methane problem, though,
can be as simple as tightening a valve
or placing a gasket or tuning an engine.
A major reason why these easy fixes
haven't been implemented isn't the cost.
It's because governments and industry
have been data-deprived,
lacking information on where
and how much is emitted.
But our ability to detect these leaks
has rapidly advanced in recent years.
Everything from handheld instruments
to sensors on aircrafts and drones.
And now there's a growing
universe of satellites
designed to locate and measure
methane from space.
That list includes MethaneSAT,
which is expected
to be launch-ready next year
and will be able to detect
and quantify methane emissions
across the globe
with unprecedented precision.
If we can find it, we can fix it.
This part is not rocket science.
It's more like plumbing.
I can't tell you enough how hopeful
that makes me for the future.
We can also reduce a lot of emissions
from the second category,
waste management,
where methane is produced
as bacteria decompose,
garbage in landfills
and sludge in wastewater.
Some of the largest landfills
receive enough trash per day
to fill more than 10
Olympic-sized swimming pools
before it is compacted.
But we can suck up
the methane from landfills
by using tubes with vacuums
and then use it to generate electricity,
because methane is an energy-packed fuel.
We can also reduce emissions
by sending some trash, like food waste,
away from landfills and instead
to composting centers
that are designed to prevent
the release of methane.
The third category, agriculture,
emits the most and remains
the hardest to address.
But there are exciting
new technologies on the horizon.
The number one source is livestock.
Some farm animals,
like the billion-plus cattle worldwide,
belch methane that was produced
when digesting plants like grass.
Reducing these emissions is possible
with higher-quality feed.
And the scientists are developing
and testing new technologies,
like feed supplements,
that can suppress methane production
in a cow's gut by at least 30 percent
with no negative effects
on productivity or quality.
Livestock manure can also produce
methane when concentrated,
but we can cover manure lagoons
and then pump manure into digesters
that can capture the methane,
which can then be used
for heat and electricity.
Another methane source is rice production.
This one crop is a staple
for half the world's population,
but the plants grow in flooded fields
that create ideal conditions
for microbes to form methane.
We can slash emissions from methane
by improving how we manage
the required water,
which can be as simple
as maintaining a shallow level of water
in the rice fields.
Implementing all of these
solutions will take work.
But people have already started to act.
Many governments, oil and gas CEOs,
landfill operators and farmers
are advancing measures to reduce methane.
But we need more,
because there is a lot of warming
that we can prevent
if we quickly deploy the full set
of affordable and available strategies.
We need standalone methane targets
as part of every company's business model,
and every country's nationally
determined contribution
as the Paris Agreement is strengthened.
Because if we succeed in a rapid,
full-scale effort to cut methane,
we have a chance to actually
experience the benefits fast,
in our lifetimes.
For example,
my colleagues and I found that we could
slow down the rate of warming
by as much as 30 percent
before mid-century.
This would help communities
and ecosystems adapt
to a changing climate
and hit the brakes on worsening
extreme events,
like wildfires in the Americas
and Australia,
and flooding in Europe and Asia.
It would also help clean up our air,
saving lives and crops,
because methane contributes
to ozone pollution.
And because some of the people
most vulnerable to the impacts
of climate change
are on the front lines
of methane emissions.
These solutions can also help reduce
the inequity of climate change,
for example, by job creation.
If we fast-forward to later decades,
acting now to cut methane
can also help protect Arctic sea ice.
This is because when methane reductions
are combined with strong actions
to cut CO2,
it becomes unlikely
that temperatures would rise to levels
that would trigger a total loss
in Arctic summer sea ice.
This is important not just for polar
communities and ecosystems,
but actually for the entire world.
I've now been talking
for almost 10 minutes,
which means that more than 700,000
metric tons of climate-warming gases
have been pumped into the atmosphere.
Now that equals the weight
of 12 million of me.
Of all this pollution,
it is the methane
that could warm the Earth the most
over the next 10 years.
But we know how to cut
these emissions in half right now
from energy, waste and agriculture.
This is the methane moment.
Because cutting methane
is the single fastest,
most effective opportunity to reduce
climate change risks in the near term.
And cutting CO2,
which will otherwise build up over time,
is the key to reducing risks
in the long term.
We need to do both
to plot a safer course
for ourselves and our children
and for generations to come.
Thank you so much.
(Applause)