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of systems and communities to adapt to such changes will vary. For example, sea
level rise will result in more frequent, or even permanent inundation of low-level
coastal areas, especially in areas that are unable to build (or cannot afford to build)
sea walls or other protections. Such incremental changes add stress to food, energy,
and water systems, which can be adapted to with greater or lesser success depending
on the local geographic and economic circumstances.
Other effects of climate change, such as more frequent and intense extreme
weather events will have very short-term as well as long-term impacts. For example,
rapid and difficult population movements are likely to be “triggered” by extreme
events are rather than incremental changes. A community already vulnerable to
flooding or severe storms may experience a single event resulting in population
displacement. Extreme weather events such as Hurricane Katrina (2005) and
Hurricane Irma and Hurricane Maria (2017) resulted in both large-scale breakdowns
in FEW systems and population movements in one of the wealthiest nations on
earth, underscoring the challenges to building resilient communities. Chapter 4 will
explore this subject in greater detail.
The combination of slow incremental changes and extreme events within the
range experienced already in human history can combine to create impacts more
significant than previously experienced. A storm surge atop higher sea level is more
likely to overtop seawalls illustrates how the likelihood that extreme events will be
even more impactful on FEW systems and human societies in the coming decades.
Total anthropogenic GHG emissions and anthropogenic GHG emissions per capita
vary significantly from country to country for many reasons. However, the use of fossil fuels for energy and changes in land use for agriculture and forestry are the two
largest anthropogenic sources of greenhouse gases. In 2010, the burning of fossil fuels
for energy accounted for approximately two-thirds of global anthropogenic GHG
emissions, or 32 (±2.7) of 49 (±4.5) gigatonnes of carbon dioxide equivalent
(GtCO 2 eq.) (IPCC 2014b). Agriculture, deforestation, and other land use changes
accounted for approximately 24% or 10–12 GtCO 2 eq. Here, emission shares are
based on their impact or global warming potential over a period of 100-years.
Therefore, energy and food systems, and to a lesser extent, water systems, are
significant contributors to anthropogenic emissions of GHGs. Efforts to mitigate
climate change will necessarily require significant changes to FEW systems.
Because FEW systems cause climate change and are impacted by it, it is appropriate
to think of climate change as mediating the interactions between FEW systems on a
global scale.
11.3 Communicating Risk, Probability, and Scientific
Confidence
Two significant challenges in communicating science, particularly climate change science, to lay audiences are the difficulty that many have in understanding: (1) scientific
uncertainty; and (2) probability-based risk. The challenges in communicating these
concepts manifest themselves concerning FEW systems and climate change.
11 Climate Change
of systems and communities to adapt to such changes will vary. For example, sea
level rise will result in more frequent, or even permanent inundation of low-level
coastal areas, especially in areas that are unable to build (or cannot afford to build)
sea walls or other protections. Such incremental changes add stress to food, energy,
and water systems, which can be adapted to with greater or lesser success depending
on the local geographic and economic circumstances.
Other effects of climate change, such as more frequent and intense extreme
weather events will have very short-term as well as long-term impacts. For example,
rapid and difficult population movements are likely to be “triggered” by extreme
events are rather than incremental changes. A community already vulnerable to
flooding or severe storms may experience a single event resulting in population
displacement. Extreme weather events such as Hurricane Katrina (2005) and
Hurricane Irma and Hurricane Maria (2017) resulted in both large-scale breakdowns
in FEW systems and population movements in one of the wealthiest nations on
earth, underscoring the challenges to building resilient communities. Chapter 4 will
explore this subject in greater detail.
The combination of slow incremental changes and extreme events within the
range experienced already in human history can combine to create impacts more
significant than previously experienced. A storm surge atop higher sea level is more
likely to overtop seawalls illustrates how the likelihood that extreme events will be
even more impactful on FEW systems and human societies in the coming decades.
Total anthropogenic GHG emissions and anthropogenic GHG emissions per capita
vary significantly from country to country for many reasons. However, the use of fossil fuels for energy and changes in land use for agriculture and forestry are the two
largest anthropogenic sources of greenhouse gases. In 2010, the burning of fossil fuels
for energy accounted for approximately two-thirds of global anthropogenic GHG
emissions, or 32 (±2.7) of 49 (±4.5) gigatonnes of carbon dioxide equivalent
(GtCO 2 eq.) (IPCC 2014b). Agriculture, deforestation, and other land use changes
accounted for approximately 24% or 10–12 GtCO 2 eq. Here, emission shares are
based on their impact or global warming potential over a period of 100-years.
Therefore, energy and food systems, and to a lesser extent, water systems, are
significant contributors to anthropogenic emissions of GHGs. Efforts to mitigate
climate change will necessarily require significant changes to FEW systems.
Because FEW systems cause climate change and are impacted by it, it is appropriate
to think of climate change as mediating the interactions between FEW systems on a
global scale.
11.3 Communicating Risk, Probability, and Scientific
Confidence
Two significant challenges in communicating science, particularly climate change science, to lay audiences are the difficulty that many have in understanding: (1) scientific
uncertainty; and (2) probability-based risk. The challenges in communicating these
concepts manifest themselves concerning FEW systems and climate change.
11 Climate Change