- The U.S. is warming fast.
But if you take a look at global climate records,
it sure does look like temperature is decreasing,
at least for the last eight years.
When NOAA released their new data in early 2023,
it went viral.
And even weathered viewers commented that this is proof
that climate change is finally moving in a cooler direction.
We'll unpack that in a bit,
but first, let's talk about long-term trends.
- The global land and ocean temperature for 2022
was 1.90 degrees Fahrenheit above pre-industrial conditions.
- But not everywhere on earth is warming
at the same speed.
And there are wide swings around the globe
from extremely fast warming
to one particularly scary area of cooling.
According to a draft government report,
the U.S. has warmed 68% faster than the global average
over the past 50 years.
And that doesn't even include Alaska,
which has warmed way faster.
- Across the lower 48,
the annual temperature has increased at an average rate
of about 0.16 degrees Fahrenheit per decade since 1895.
But that rate of increase is 0.44 degrees Fahrenheit
since 1980.
- So in this episode, we're gonna figure out
why the average temperatures were dropping
over the past eight years,
find out which parts of the globe are warming fastest,
and at the end, we'll call up a resident
of the fastest warming county in the U.S.
to hear what it's like.
Oh, and it turns out that there's an area in the U.S.
that hasn't been warming at all, so stay tuned.
Okay, first, what's up with the dropping temps?
- The earth is not cooling.
So here's the thing.
There can be year to year variability,
that means those ups and downs from year to year.
- We all understand this on a smaller scale
when it comes to changing seasons, right?
We know that nature doesn't operate in straight lines.
As spring turns into summer,
the temperature doesn't rise incrementally every day.
It might be warm on April 1st, then snow on April 8th,
but no one doubts that August will be hot.
And we see this with climate change, too.
Temperature pulses higher, then levels off,
then pulses again.
But choose the right eight years to analyze
and you'll see a downward trend.
2016 was 1.19 degrees above pre-industrial levels,
and 2022 was only 1.07.
For reference, the Paris Agreement aims
to keep the global average temperature rise
between 1.5 and 2 degrees Celsius.
Even inside that range,
we may hit some very disruptive tipping points,
including the loss of coral reefs
and abrupt permafrost thaw,
but no one lives in an average.
- Every continent in the world is warming,
but the rate of change of that warm can differ
from place to place.
- So where is warming fastest
and where is warming the slowest?
There are two big picture factors at play:
latitude and oceans.
First, high altitudes in the far north are warming fastest
largely because of sea ice.
As temperatures rise, sea ice melts exposing dark water
that absorbs more solar radiation,
which causes more warming,
and the cycle continues.
Now, the cycle won't continue forever.
Once enough sea ice has melted,
this Arctic amplification will slow down
and the Arctic will warm at a rate more similar
to the rest of the globe.
But for now, if you're farther north,
you're probably warming fast.
Second, water reflects more of the sun's energy
than land does, and it has a far higher heat capacity.
So it takes a lot more energy to raise ocean temperatures
than land temperatures.
That means our large continents are warming faster
than the oceans, and guess what?
That's where humans live.
Put this together and you get this generalization.
Large land masses in the north are warming fastest.
Most of the earth's land masses are in the mid-latitudes
and northern hemisphere.
So those regions are warming faster than southern regions,
but which continents are warming the fastest?
Europe is the fastest warming continent
at 0.47 degrees Celsius of warming per decade since 1980,
and Asia comes in a close second.
Globally, there are some unusual hotspots as well.
A mysterious pocket off the coast of Uruguay
and Argentina has warmed twice as fast
as the global average,
causing algae blooms and mass die-offs of marine species.
There also seems to be a similar hotspot
in the North Atlantic along the coast of Delaware to Maine.
These hotspots seem to be largely driven
by shifting ocean currents that bring warmer water
to unlikely places.
Interestingly, some places are warming slower
for unexpected reasons.
Parts of Antarctica have slowed warming
in part because of the ozone hole,
and India is warming less than its surroundings,
because of severe pollution keeping out solar radiation.
And that cool spot in the Arctic,
that's caused likely by Greenland's melting ice.
So that brings us back to the U.S.
Researchers at the University of Massachusetts found
that the lower 48 is expected
to reach two degrees of warming, 10 to 20 years
before the globe as a whole.
From previous episodes,
we know that the Western U.S. is getting drier,
and it turns out precipitation plays a big role
in which regions are warming.
Vegetation, trees, and moisture can help mitigate warming,
while drought can make it worse.
- [Karin] But we are seeing parts of the west
and the northern tier warming faster
than the rest of the country.
And a lot of the driver for this is that drought periods
in the west are becoming more entrenched,
and as regions that are dry become more dry,
that means there's less moisture in the soil.
And so, you'll actually have higher temperatures
during the day.
We're talking parts of the interior Rockies,
portions of, you know, Oregon, California,
as well as parts of the Northern Tier, Minnesota, Montana.
- [Maiya] We also know that the northeast is warming faster
than the U.S. average,
and is expected to reach 3 degrees Celsius of warming
when the globe as a whole reaches two.
- Higher latitudes are warming faster.
Winter is the fastest warming season
for the northern hemisphere, certainly for the U.S.
- This means extreme winter warming all the way
from Montana to Maine.
One reason for this is
that snow pack is melting earlier in the season.
Fewer days of snow cover means more sunlight
that absorbs into the ground warming the region.
We'll take a look at the fastest warming county in the U.S.
at the end of the episode,
but first, we wanted to know where is warming the slowest?
- [Karin] If you look from the Gulf Coast
to about the mid-Mississippi Valley,
so sort of that south central portion of the lower 48,
there's like virtually no trend in warming or cooling
across that 128 year period of record.
- Some scientists believe the polar vortex
can help explain this anomaly.
The warming Arctic has made the jet stream wavier,
allowing cold polar winds to escape to the southeast,
creating a cooling effect in the winter and spring months.
Scientists have also connected this warming hole
to periodic thick clouds and high soil moisture
that help keep daytime temperatures down.
And while there was no warming trend
over the past 120 years,
the past 40 years do show temperatures beginning to rise.
So we know climate change is experienced pretty differently
around the world, but it also varies from year to year.
And it turns out that a big reason
for the variation comes back to El Niño and La Niña.
- In an El Niño year,
the waters in the Eastern equatorial Pacific
are warmer than average,
and in the La Niña year, they're cooler
and that helps to drive various weather systems
across the globe.
So we often use the metaphor of like being on an escalator,
and that escalator is going up.
And during an El Niño year,
it's like standing on your tippy toes on the escalator
and a La Niña is like crouching down on the escalator.
The overall direction is still up,
but you're seeing year to year variances.
And in fact, the last three years,
we've been in a consistent La Niña,
which would be sort of a cooling.
And what we've seen is really kind of the leveling off,
but it's keeping pace, you know,
in the top 10 and close to top 5, each of those years.
- So what about the future?
- It is very likely that 2023 will end
among the 10 warmest years on record.
And if it does, then the 10 warmest years
on record would have been the last 10 years
from 2014 all the way to 2023.
If an El Niño were to form at the end of 2023
in continuing to 2024,
there is a high chance that the year 2024 could rank
among the warmest years on record.
- And that has big consequences,
especially for regions that are warming fast,
which brings us to the fastest warming county in the U.S.,
North Slope Borough and Alaska home to the native community
of Borough now called Utqiagvik.
Since 1980, it's warmed 0.72 degrees Celsius per decade,
significantly outpacing the rest of the U.S.
We called Eben Hopson
to learn a little more about what it's like living there.
He's 23, a subsistence hunter and fisher,
and advocate for his community.
His Iñupiat ancestors have lived in the region
for thousands of years with a constantly changing climate,
but the current rate of change is unprecedented.
- Living here in the Arctic,
you know, hunting, fishing, whaling,
trying to survive here in the Arctic
and not really expecting that change could come so quickly.
It's scary because,
one, hunting's gonna be different this year;
two, thinking about the future,
the conditions that I teach the future generation
and will not be the same as the conditions are today.
- And there are concrete examples
of what near four degrees of warming means.
- All of the houses here on the arctic slope
and they're built on stilts,
maybe eight to 10 feet in the ground in the permafrost.
And once the permafrost around those posts melt,
then that house kind of shifts to one side
and it's hard to open doors, hard to open windows
until you you correct the sinking pilot.
- Eben does remember this from his early childhood.
- But it's more prevalent now than it was then.
- Traditionally, his community gets ready
for the spring whale hunt in April
when snow buntings arrive.
But this important marker
of the season seems to be changing.
- Today is April 13.
I haven't seen a snowbird yet.
Once I see a snowbird,
then that'll tell me the the bowhead whales are here
and they're ready to be harvested, ready to feed the people.
- He told us that the bird
and whale timing just seems to be out of sync,
and whaling is getting less consistent.
- I mean, yeah,
there's beef, chicken, and pork at the store,
but that's not as healthy and nutritional
as fresh, locally-sourced bowhead whale muktuk and meat.
- So what about where you live?
Are parts of your life changing in a warming climate?
Is your your city warming faster or slower than average?
Let us know in the comments and we'll see you next time.
Our weather is changing
from longer hotter heat waves to more intense rainstorms
to mega fires and multi-year droughts.
The U.S. is experiencing the full range
of impacts from climate change.
Find out what people on the front lines are doing
to combat weirder weather in Nova's latest episode,
"Weathering the Future".
The full episode is live
on Nova's YouTube channel right now.
Check it out at the link in the description
and tell them Weathered sent you.