by Ananya Sen
Climate change
has been hotly debated in the past couple of decades, and while the evidence is
clear that it’s a big problem, sometimes it’s hard to picture that in your head.
But the visual evidence that scientists have gathered can be even more
compelling than the climate change projections – take a look for yourself. Click on and move the big circle to slide the line dividing these two overlaid pictures of a glacier in 1909 and 2018, and compare and contrast:
Image credit: Eduard Spelterini/Kieran Baxter/University of Dundee
In October 2018
a team
of photographers recreated a 1909 expedition that took stunning pictures of the
Mer de Glace glacier in the French Alps. Eduard Spelterini, a Swiss aviation
pioneer, took the original pictures during his voyage in a gas-filled balloon.
The 2018 team embarked on the same trip to document the changes the past
century has brought. What used to be an impressive glacier has now largely been
replaced by an empty valley and debris.
That illustrates
what the Intergovernmental Panel on Climate Change (IPCC) released in its report on climate change and its predictions
for the next few decades in October 2018. The report is sobering to say the
least. Several land and ocean ecosystems have already changed due to global
warming. For example, for an increase in 1.5 °C 6% of insects,
8% of plants, and 4% of vertebrates are projected to lose over half of the area
they identify as home. A direr situation awaits coral reefs, which are
projected to die out almost completely for the same temperature change. ScienceSeeker’s
picks for 2018 include many articles that highlight such consequences of
climate change.
Climate change
has obviously changed marine ecosystems. Some reef
fish have evolved to depend on coral reefs for food and protection. These
fish are smaller and have less defensive spines, enabling them to live among
the corals instead of the sea bed. Many reef-dwelling fish have vanished with
the decline in reef ecosystems. Sea
turtles represent another group of animals that have been adversely
affected due to climate change. Although their ancestors survived the
extinction event that wiped out dinosaurs, the modern descendants are among the
most threatened groups of vertebrates in the world. Currently 61% of the
population is threatened or extinct, which can have ominous consequences for
their diverse ecosystems.
Even land
inhabitants that have been flourished for centuries are now struggling. For
example, more than half of Africa’s giant baobabs,
some of which are 1,500-2,000 years old, have died between 2006 and 2017. Other
organisms have displayed the effects of climate change in a different way. Birds
sing to attract mates and establish territories. The timing of the bird songs
depends on the breeding season. Recent recordings by scientists have shown that
the timing has been moving up four days per decade. This can result in a
mismatch for migratory birds whose breeding and feeding patterns might become
out of sync with their surroundings, leading to a population loss.
The effects of climate change will
also have adverse effects on humans. It has been predicted that global warming will
increase the number and intensity of tropical
storms. For example, in New York City the return period will be reduced
from 25 years today to five years in the next three decades. Analysis of the
tropical cyclone data from 1980 to 2016 has shown a significant global increase
in the number of storms with maximum speeds of 175 km/h. More troubling is the
observation that the number of storms with speeds of 200 km/h has doubled, and of
those of 250 km/h has tripled. Climate change is also shifting the location of the
storms and expanding the affected areas. Regions near the poles that have been
historically less threatened by these storms are going to be at risk.
Although the outlook is grim, all is
not lost. The Paris agreement has made countries aware of the steps that need
to be taken to reduce global warming, prompting efforts to reduce carbon
emissions. To that end, California
is seeking to create a blueprint for others to follow. In September 2018 the
California Governor issued an executive order calling for the California
economy to become carbon neutral by 2045. The measures include transitioning to
clean energy, using electric cars for transportation, increasing carbon
sequestration by farming, and changing livestock feeds to reduce methane
emissions from cattle.
The most important step for all of
us is to recognize
that the reality of climate change is going to affect our generation. It is
easy to feel resignation and remain idle but we need to take active measures,
no matter how small. It has been estimated that only 100 companies are
responsible for 75% of the global emissions. Together we can pressure these
companies into making environmentally conscious decisions. We can also aim to
reduce our own carbon footprints and adjust our living standards. It has been
said that necessity is the mother of all invention. By reminding ourselves that
the fate of the Earth and its future rests on our shoulders, humans can drive
the changes required to bring our planet back from the brink of collapse.
Ananya Sen is a grad student in microbiology at University of Illinois, Urbana-Champaign. She spends 80% of her time working on oxidative stress in the Imlay lab and the remaining 20% of her time blogging about science, exploring food, taking care of her dog.
