Page 9 - Respond 2019 Magazine

Respond

A pregnant woman suffering from malaria. As the climate changes, mosquitoes will spread disease to new areas (Pic: Flickr/hdptcar)

5. Global warming is already impacting people and ecosystems. compared to 1.5C. That is equivalent to the land area of Iran,
The risks at 1.5C and 2C are progressively higher. Mexico or Algeria. In a vicious cycle, thawing permafrost
releases methane, a greenhouse gas.
6. Lines on the feasibility of holding the temperature rise
to 1.5C and the importance of considering sustainable 12. The probability of a sea ice-free Arctic summer increases
development have been cut from this section. They are tenfold from once a century at 1.5C warming to once a
considered in detail elsewhere, but it shows a lack of decade at 2C. Marine ecosystems will be hit by ocean
consensus on the high-level conclusions. acidification and warming. 2C virtually wipes out coral reefs,
compared to a 70-90% decline at 1.5C.
Impacts and threats
7. There will be worse heatwaves, drought and flooding at 2C 13. Farming and fishing communities will be hit hardest by these
compared to 1.5C. A previous version characterised these impacts, particularly in the Arctic, drylands, islands and the
as “substantial differences in extremes”. That wording poorest countries. Limiting global warming to 1.5C cuts the
has been replaced with “robust differences in regional number susceptible to poverty and climate-related risks by
climate characteristics”, in a win for the US, which argued up to several hundred million by 2050.
“substantial” was too subjective.
14. That extra half a degree of warming is mostly bad for health.
8. Sea levels are expected to rise 10cm higher this century It expands the range of mosquitoes carrying diseases like
under 2C of warming than 1.5C. That exposes an extra 10 malaria and dengue, and heat makes a whole range of
million people to impacts like coastal flooding and saltwater conditions more deadly.
getting into their fields and drinking water supplies. Slower 15. The quantity and quality of staple crops suffers under 2C
warming buys them time to adapt.
warming compared to 1.5C, as do livestock. That is bad for
9. Over centuries and millenia, sea levels will continue rising the availability of food in many parts of the world.
after temperatures have stabilised. The collapse of ice sheets 16. Economic growth is expected to suffer as a result of the
in Greenland and Antarctica could lead to rises of several impacts of global warming, all else being equal. This
metres.
assessment does not attempt to balance that with the costs
10. One of the most striking quantitative findings concerns the and benefits of cutting emissions and investing in resilience
loss of biodiversity. It predicts the proportion of species that to climate change impacts.
will lose half their geographic range. Out of 105,000 species 17. There are lots of options to protect against the impacts of
studied, the rate doubles between 1.5C and 2C warming to global warming, from sea walls to drought-resistant crops.
16% for plants and 8% for vertebrates, and triples to 18% for But these adaptations have limitations and some vulnerable
insects.
populations face losses. The Paris Agreement acknowledged
11. An estimated 1.5-2.5 million square kilometres more this “loss and damage”, but the UN process has yet to yield
permafrost will thaw this century under 2C warming concrete support for the victims.

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