David Wallace-Wells is determined to relieve us of any
delusions about the changes being wrought by human-created climate change. He collects what are the known-knowns and the
known unknowns and scares us with suggested unknown-unknowns in his book The Uninhabitable Earth: Life After Warming. Complacency is no longer an option. These are his opening words.
“It is
worse, much worse than you think. The
slowness of climate change is a fairy tale, perhaps as pernicious as the one
that says it isn’t happening at all, and comes to us bundled with several
others in an anthology of comforting delusions: that global warming is an
Arctic saga, unfolding remotely; that it is strictly a matter of sea level and
coastlines, not an enveloping crisis sparing no place and leaving no life
undeformed; that it is a crisis of the ‘natural’ world, not the human one; that
those two are distinct, and that we live today somehow outside or beyond or at
the very least defended against nature, not inescapably within and literally
overwhelmed by it; that wealth can be a shield against the ravages of warming;
that the burning of fossil fuels is the price of continued economic growth;
that growth, and the technology it produces, will allow us to engineer our way
out of environmental disaster; that there is any analogue to the scale or scope
of this threat, in the long span of human history, that might give us
confidence in staring it down.”
“None
of this is true.”
What is true is that global
warming is accompanied by so many changes and effects that we cannot possibly
understand how they interact and provide feedback that drives further changes and
effects. Wallace-Wells puts it this way.
“THE
ASSAULTS WILL NOT BE DISCRETE—This is another climate delusion. Instead, they will produce a new kind of
cascading violence, waterfalls and avalanches of devastation, the planet
pummeled again and again, with increasing intensity and in ways that build on
each other and undermine our ability to respond, uprooting much of the
landscape we have taken for granted, for centuries…”
A litany of the horrors in store
for us if we do not mend our ways is presented.
In so doing, Wallace-Wells points out some unknown-unknowns that have
recently transitioned to known unknowns.
This is an effective way of supporting his claim that what will assault
us will be a “cascade” of effects.
What is of interest here is the
recently discovered fact that a rising level of carbon dioxide may be
beneficial to bulk plant growth, but it can be deleterious to the production of
the nutrients that humans need. Or, as Wallace-Wells put it:
“Everything
is becoming more like junk food.”
Carbon dioxide is a plant
nutrient. Just as our bodies respond to
a change in nutrient levels so do those of plants. What higher carbon dioxide levels do, at
least to some critical food sources, is increase the levels of carbohydrates
produced at the expense of proteins, minerals, and vitamins. Not only will our warming earth make the
production of crops more difficult, the crops produced will be of less
nutritious (“more like junk food”) for reasons we hadn’t anticipated. Helena Bottemiller Evich provides a
concise summary of how scientists, ever so slowly, became aware of this
unknown-unknown in The great nutrient collapse.
Evich tells the story of Irakli Loladze, a mathematician with
an abiding interest in biology. Loladze
was introduced to a biological paradox as a graduate student in 1998.
“Zooplankton are microscopic
animals that float in the world’s oceans and lakes, and for food they rely on
algae, which are essentially tiny plants. Scientists found that they could make
algae grow faster by shining more light onto them—increasing the food supply
for the zooplankton, which should have flourished. But it didn’t work out that
way. When the researchers shined more light on the algae, the algae grew
faster, and the tiny animals had lots and lots to eat—but at a certain point
they started struggling to survive. This was a paradox. More food should lead
to more growth. How could more algae be a problem?”
“The biologists had an idea of
what was going on: The increased light was making the algae grow faster, but
they ended up containing fewer of the nutrients the zooplankton needed to
thrive. By speeding up their growth, the researchers had essentially turned the
algae into junk food. The zooplankton had plenty to eat, but their food was
less nutritious, and so they were starving.”
Loladze knew that accelerated growth of algae could also
be caused by increasing the level of carbon dioxide available. Would the same effect be observed in that
case? If so, a similar effect would be occurring
planet wide as levels of carbon dioxide continued to rise. He discovered that there was very little data
available to address this hypothesis, but what there was suggested that it was
true. However, the relevant scientific
community had not even raised the concern.
It would fall on him, as a sideline to his main work, to push the issue.
What was known was that the nutritional quality of many
of our crops had declined over the time between 1950 and 1999. In 2004 a study of this data was published
detailing this decline: Changes in USDA food composition data for 43 garden crops, 1950 to 1999. It included
this summary.
“As a group, the 43 foods show
apparent, statistically reliable declines (R < 1) for 6 nutrients (protein,
Ca, P, Fe, riboflavin [vitamin B2] and ascorbic acid [vitamin C]), but no
statistically reliable changes for 7 other nutrients. Declines in the medians
range from 6% for protein to 38% for riboflavin.”
These investigators assumed that these degradations could
be explained by the agricultural market shifting to higher yield varieties of
plants that produced fewer nutrients.
This conclusion could not rule out a role for carbon dioxide in the
process, and Loladze kept pushing the issue, finally exciting the interest of
other researchers. One of the approaches
was to examine the evolution of a wild plant that was unaffected by man-made
decisions.
“Goldenrod, a wildflower many
consider a weed, is extremely important to bees. It flowers late in the season,
and its pollen provides an important source of protein for bees as they head
into the harshness of winter. Since goldenrod is wild and humans haven’t bred
it into new strains, it hasn’t changed over time as much as, say, corn or
wheat. And the Smithsonian Institution also happens to have hundreds of samples
of goldenrod, dating back to 1842, in its massive historical archive…”
“They found that the protein
content of goldenrod pollen has declined by a third since the industrial
revolution—and the change closely tracks with the rise in CO2.”
Carbon dioxide as a cause of nutrient collapse can now be
studied more directly after researchers developed what is called the FACE
technique.
“Researchers use a technique
that essentially turns an entire field into a lab. The current gold standard
for this type of research is called a FACE experiment (for “free-air carbon
dioxide enrichment”), in which researchers create large open-air structures
that blow CO2 onto the plants in a given area. Small sensors keep track of
the CO2 levels. When too much CO2 escapes the perimeter, the
contraption puffs more into the air to keep the levels stable. Scientists can
then compare those plants directly to others growing in normal air nearby.”
If nutrient collapse was occurring because of rising CO2
levels, the most affected would be people possessing limited food security
where malnutrition is a constant threat.
Many such people depend on rice as the main food source. FACE studies were performed on rice varieties
to determine what effect a CO2 level consistent with what might be reached in
the next few decades would have on nutrition: Carbon dioxide (CO2) levels this century will alter the protein, micronutrients, and vitamin content of rice grains with potential health consequences for the poorest rice-dependent countries.
“As of 2013, approximately 600
million individuals, primarily in Southeast Asia [the countries of Bangladesh,
Cambodia, Indonesia, Lao People’s Democratic Republic (PDR), Madagascar,
Myanmar, and Vietnam], consume ≥50% of their per capita dietary energy and/or
protein directly from rice…”
“When grown under field
conditions at these anticipated [CO2] a significant reduction (an average of
−10.3%) in protein relative to current [CO2] was observed for all rice
cultivars…Similarly, significant reductions in iron (Fe) and zinc (Zn) were
also observed (−8.0 and −5.1%, respectively) among all rice cultivars tested…”
These degradations will be on top of the loss of
nutrients already caused at our current CO2 levels. As usual, the wealthy produce climate change,
and the poor will be the first to suffer the consequences.
Evich summarizes the results of studies beginning to
emerge as these issues attain a higher priority and more data becomes available.
“Earlier this summer [2017], a
group of researchers published the first studies attempting to estimate what
these shifts could mean for the global population. Plants are a crucial source
of protein for people in the developing world, and by 2050, they estimate, 150
million people could be put at risk of protein deficiency, particularly in
countries like India and Bangladesh. Researchers found a loss of zinc, which is
particularly essential for maternal and infant health, could put 138 million
people at risk. They also estimated that more than 1 billion mothers and 354
million children live in countries where dietary iron is projected to drop
significantly, which could exacerbate the already widespread public health
problem of anemia.”
These conclusions result from an effect once deemed too
small to be of interest. Is this the
extent of the effect, or are we considering the tip of an iceberg? Remember the tale of the zooplankton; bad
things can happen when one plays with nutrition levels. And how many other unexamined effects and
feedback loops will be excited as the climate warms and changes?
Let us recall Wallace-Wells’ initial warning.
“THE
ASSAULTS WILL NOT BE DISCRETE—This is another climate delusion. Instead, they will produce a new kind of
cascading violence…”
Complacency is no longer an
option.
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