The projected impact of climate change on dust generation is seldom considered in the planning and framework of the design for pavement construction, mining activities, recreational facilities, agricultural activities just to mention a few. Often times, the approach taken is based on the past and present without much investment in the future. Given the recurrence and frequency of natural phenomenon such as floods leading to elevated soil moisture susceptibility and droughts resulting in more dry seasons consequentially the future must be taken into account in the initial stages of any project. Of particular interest to our conversation is dust in its various forms and how much more prevalent it will be as a result of the effects of climate change. We pose three key questions:
- What is the worldview on climate change and dust generation?
- What is the Australian view on climate change and dust generation?
- Of the products currently available for dust suppression how do they meet sustainable development goals
The
article will
evaluate and
seek to answer
the questions
whilst
highlighting
the synergy
with
sustainable
development in
tackling dust
generation for
the future
based on
climate
change.
What
the modelling
can show
us?
Predictive
modelling from
climate models
suggests a rise
in drought
conditions
resulting in
unmatched
aridity in the
next half
century. The
burden on
health and the
society is
forecasted to
be devastating
and
unfortunately
it’s not
always the case
of forewarned
is forearmed as
for most of the
world.
Globally, the
predictive
tools for
climate change
and its effects
on dust
generation in
the last few
years have been
faced by large
uncertainties
in dust
modelling. For
example
projection of
American
dustiness in
the late 21st
century did not
yield any
specific
information for
the United
States given
the difficulty
for models to
properly
reproduce
observed dust
variability
over North
America.
Presently, they
have been
suggestions for
application of
modulated dust
source strength
to fit the data
however this
has limitations
in projection
of future dust
change. Most
recently,
researchers
from Princeton
University
evaluated key
controlling
factors of dust
activity using
satellite data.
They used key
projected
changes
controlling
these factors
from climate
models to
project future
dust activity
due to climate
change with
their model
parameters
working on a
worst-case
scenario of
extreme
droughts and
associated dust
generation.
What
the data tells
us?
Over
the past five
decades,
climate change
detection in
Australia has
improved
remarkably.
Observations in
maximum daytime
temperatures
and average
minimum
night-time
temperatures
depicts a rise
almost all over
the country.
Annual rainfall
rose in the
northwest as a
summer
singularity but
reduced in the
southwest. In
addition, rise
in warming due
to greenhouse
gas
concentrations
and decreased
rainfall in
southwest
Western
Australia is
attributed to
natural climate
variability and
land-use
changes. Marked
increase in
summer rainfall
in northwest
Australia was
due to aerosols
resulting from
human
activities. The
climate change
monitoring in
Australia has
been made much
easier with
availability
data sets from
50 to 200
stations
distributed
evenly from
over the
Australian
continent and
prepared by the
Australian
Bureau of
Meteorology.
Generally,
drought
conditions
obtained from
the
precipitation
minus
evaporation
have been more
common. The
recent droughts
of 1994 and
2002 did not
show
significant
changes in
total
precipitation
but
temperatures
have been very
high in the
recent droughts
in
Australia.
Intensification
of dust
generation as a
result of
drought can be
examined from
variation in
precipitation,
surface wind,
surface
bareness.
Precipitation
which is also
related to soil
moisture
reduces dust
generation by
dislodging
airborne dust
and increasing
soil moisture
in the dust
source area, it
also curbs the
rise of dust
particles due
to winds. A
lack of
precipitation
owing to
drought
therefore
favors dust
generation with
dust events
correlated to
frequency in
dry episodes.
Surface wind is
related to
transport of
dust as a
result of wind
speed leading
to increase in
dust emissions.
Surface
bareness
considers
mostly the area
covered by
vegetation and
how it
contributes to
reducing soil
erosion by
wind. These
variations are
described
broadly but an
example in
farming
considers the
effect of
change in land
use or cover
for instance
from grasslands
to
non-irrigated
croplands, the
lack of
vegetative
cover, improper
farming methods
also contribute
to dust
generation and
can be
accelerated by
climate change.
All these
factors lead to
intensification
of dust
generation,
which in turn
affects air
quality.
UNCSD
– Kicking
Goals
The
follow-up of
the 2012 Rio+20
United Nations
Conference on
Sustainable
Development has
driven the
post-2015
development
agenda through
coordinated and
concerted
strategies and
actions to
minimize
potential
trade-offs and
conflicts
whilst
maximizing
synergies to
contribute to
multiple
Sustainable
Development
Goals.
Reduction of
dust generation
in a more
controlled
environment
such as a mine
or farm is
interlinked to
achieving
development
goals and
targets. For
example use of
environmentally
friendly dust
suppressants
enables
achievement
of:
- Goal 3: good health and well-being
- Goal 8.4: improve progressively global resource efficiency in consumption and production and endeavor to decouple economic growth from environmental degradation
- Goal 8.8: promote safe and secure working environments
- Goal 12.4: achieve the environmentally sound management of chemicals and all wastes throughout their life cycle
Looking
forward,
looking
back
The
view on climate
change and dust
generation
varies from one
country to the
other. A lot of
this is due to
the
disagreement
regarding the
level that
human
activities are
driving climate
change.
Regardless of
the why, the
effects of
climate change
are universal,
and incidence
of dust
generation is
correlated to
natural
phenomenon
culminating
from climate
change.
Australia like
any other
country has
experienced
changes in
climate and
inevitably this
has led to
further
increase in
dust
generation.
Environmentally
friendly dust
suppression
products meet
the sustainable
development
goals in
promoting safe
working
environments
through sound
management of
chemicals
obtained from
green
feedstocks and
harness the
power of the
circular
economy
approach to
dust
mitigation.
Climate change
mitigation
strategies must
factor in air
quality
co-benefits to
application of
effective dust
suppression
methods as part
of the
framework with
assessments
from an
economic,
health and
environment
point of view.
Imperative to
the policy
making is
consideration
of past climate
changes and how
the global dust
cycle responded
to projected
future climate
changes. In as
much as the
future is
important the
past can also
be used to
benchmark and
even improve
climate
modelling tools
and
sensitivities
to enhance
prediction
capabilities of
the future
climate
models.
REFERENCES
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