Page 19 - Our Land

OUR LAND 19

Projections of changing annual rainfall
But these predictions refer to a far away future. over the southwestern Cape for the period Future of food
Why should it matter to us how hot it’s going to be
in 2080? of 1971 to 2099
Because it’s happening already. We’re already well on
the road to the “hot mess”. In 2014, University of Cape Artificial intelligence and the
Town climate scientists Neil MacKellar, Mark New and KEY internet of things are making it
Chris Jack crunched the data for the 50 years from Tave – Average temperature
1960 to 2010, and they found that “maximum possible for farmers to make the
temperatures have increased significantly throughout RCP – Representative concentration pathways. There are four (2,5; agricultural sector more sustainable
the country for all seasons, and increases in minimum 4,5; 6,5 and 8,5) greenhouse gas concentration trajectories – not – and our food more nutritious,
temperatures are shown for most of the country”. emissions – this model uses two of them
They said that “a notable exception is the central writes Johan van der Merwe
interior, where minimum temperatures have decreased RCP 4.5 – Assumes greenhouse gas emissions peak around 2040,
significantly”, which means that, in the interior, then begin to decline f you have ever had a veggie garden, chances are you
daytime temperatures were going higher, while night- RCP 8.5 – Assumes greenhouse gas emissions continue to rise have had variable success due to any number of
time temperatures were going lower. throughout the 21st century Ifactors, from the amount of sun your veggie patch
This has important implications for all sorts of gets, to the weeds that take over during your holidays.
things, from plants and animals to infrastructure – Perc – The rate at which rain is absorbed into the ground and what Chances are, you also realised just how difficult it is to
think cement or tarmac that’s stressed by contracting is available for evaporation keep your vegetables alive during a drought. For many
under cold and expanding under heat. farmers in the Western Cape, the dreadful thought that
the taps would run dry earlier this year became a reality,
HEAT STROKE AND ECOSYSTEM LOSS but us city folk still had access to all our usual food
And us, of course. All mammals – and humans are stuffs, though we did pay a little more than usual for
no exception – maintain a tight temperature range. In produce such as meat, onions and potatoes.
our case, it’s about 37°C. As any parent who has The golden ticket for commercial farmers trying to
anxiously watched a sick child’s fever knows, just a mitigate these “veggie patch” challenges is their ability to
small shift outside that range spells trouble. deal with risks through good, timeous decisions that are
When the ambient temperature (the temperature of aided by technology.
the environment around you) goes above 38°C, you’re Some farmers have chosen to use technology that limits
at risk of heat exhaustion. At 40.6°C and more, heat or even nullifies the influence of nature, much like the
stroke becomes a risk. massive indoor hydroponic farms in China and Europe
This can be deadly – more than 40 Japanese people that you see online.
died in persistent temperatures of 38°C since the Other farmers, like the followers of the hugelkultur
beginning of July. principles or organic farmers, have chosen to put systems
In fact, things get serious long before that, as quite and technologies in place that allow nature to be almost
mild increases in heat carry off the vulnerable – the Source: CSIR Graphics24 completely in control of the production cycle.
very young, the ill and the elderly. In a European These are the two extremes of agriculture and the
study, the death rate started to rise above normal at Projections of rapidly rising surface distance between them will possibly grow larger in future,
32.7°C in Athens. temperatures over Africa but in between these extremes are the businesses that
Livestock suffer similarly in the heat and, as produce more than 90% of the food we consume daily –
Professor Scholes noted, in many areas we’re already Projected changes in average temperatures (°C) in southern Africa for the average South African commercial farmer.
“quite close to the level where livestock is not really 2080 to 2100 for RCP4.5 (left) and RCP8.5 (right) The recent drought could have been much worse as far
viable”, so we don’t have much margin to play with. as food security goes in the Western Cape, but the
We can move some livestock to warmer areas that resilience of farmers ensured that we wanted for nothing.
were previously too cold for them, but it’s a slim Local farmers vary in the degree of technology they
budget of land. apply, but, ultimately, the long-term sustainability and
Wildlife face the same predicament, except they current realities are the drivers of their decisions and so
can’t move as easily because they need to take a the farmers were well prepared to deal with the drought.
whole biome with them – food plants, insects, birds
and all. This is one reason the Kruger National Park MITIGATING THE DROUGHT
faces the prospect of losing two-thirds of its species, In the Western Cape, some farmers using irrigation had
a dramatic loss that will affect tourism and the as little as 50% of their allotted quota for water over the
ecosystem. past summer. Apart from implementing water-saving
Recent major flooding in the park was “due to an irrigation systems such as drip irrigation, they also started
increasing frequency of cyclone-driven extreme floods”. using soil moisture probes, which collect hourly data on
This has also been very damaging to the rivers in the the amount of moisture in the soil.
park, and to the species that depend on their From this, the farmers could determine the rate at
ecosystem services, according to UK researchers, who which their plants used moisture, exactly when irrigation
reported their work earlier this year. was needed and how much to irrigate at a time.
But there are some species that are prospering and Though farmers used much less than the optimal
will continue to do so with climate change. Microbes amount of water to reach the full production potential of
like cholera, for example, will be able to spread rapidly their crops – in some cases only half – the production
in polluted waters and in floods; rats (and other pest losses in most of the irrigated commodities, such as
species), the populations of which are already grapes, deciduous fruit and vegetables, were only down by
exploding in urban South Africa, love the warmth and between 10% and 20%, and 30% in the worst cases.
the rapid growth of our cities. The information gathered from the example above, as
Already, two-thirds of South Africans live in cities well as other sources of data collection, is the crux of
and predictions are that, by 2050, three out of four of precision farming, and ever more farmers are making use
us will be urbanites. of the internet of things, a network where all the
And cockroaches. Cockroaches grow more active machines on the farm are interconnected, collecting data
with rising temperatures – if that’s not a good reason as they go and performing tasks informed by algorithms
to fight climate change with all your might, I don’t derived from processing this data.
know what is.
Well, maybe there is the effect on your lungs, on FROM DATA TO DECISIONS
respiratory health: “Climate change may have a direct Aerobotics, a Cape Town-based company, is one of a few
effect on air pollution in South Africa,” Dr Caradee companies collecting and processing this data on behalf of
Wright and her colleagues wrote in the SA Medical farmers. By developing intricate algorithms from this data,
Journal in 2014. Aerobotics is able to enable machine learning, or artificial
“It is likely that surface-level ozone and particulate intelligence (AI).
matter, two factors that contribute greatly to air James Paterson, co-founder and chief executive of
pollution, could be most affected by climate change.” Source: CSIR Graphics24 Aerobotics, says: “Once the first machine has learnt what
And, as the warmer growing season expands, a tree looks like, every other machine in the network
pushing winter back so that spring comes sooner and immediately has the same knowledge. This can then be
sooner, so the pollen season, with all its discomforts extrapolated to identify early signs of pest and disease
for allergy sufferers, gets longer. HOPE IN THE SOIL problems, growth problems or signs of stress in individual
Challenges to food security, to human health, to trees, enabling farmers to make better decisions more
Africa’s iconic animal species (and thus to tourism and Fixing our soil fertility is one possible way to keep climate change timeously, increase yield and quality of produce, and
the game industry), to growing cities and shrinking bearable – as the soils recover, they not only regain their capacity to increase overall health of their trees or plants, decreasing
agricultural zones … We’re firmly on the road to this hold CO 2 , they begin to actively pull additional CO 2 out of the the need for chemical intervention.
future, and some of the scary stuff is inevitable, atmosphere. The science on this is quite exciting. “In the same way, Blue River Technology in the US has
scientists say. A recent study published by the National Academy of Sciences developed AI that can distinguish between weeds and a
Citizens and government alike need to pay attention claims that regenerative farming can sequester 3% of our global carbon soya plant. Cameras are installed on sprayers and, as it
to what science says about the years just ahead of us; emissions. An article in Science suggests it could be up to 15%, and moves through a field of soya, often driverless and guided
we need to be fearless advocates for firm and decisive new research from the Rodale Institute in Pennsylvania in the US, by GPS, the AI component identifies the weeds and
action on the international stage. And, at home, South though not yet peer reviewed, suggests sequestration rates could be as herbicide is applied only to the weeds,” says Paterson.
Africans need to be agile, innovative and creative to high as 40%. In other words, regenerative farming may be our best shot The beauty of agriculture is that the more water and
find ways to live in this new world. It’s a clarion call at actually cooling the planet. soil health is improved, the higher the quality and
to action – not just to fight climate change, but to And it comes with a very useful side-effect – regenerative methods nutritious value of the product will be. AI makes this
adapt to it and live within it. actually produce higher yields than industrial methods over the long progress possible and consumers, thanks to these
. This article is part of a series on climate and food term by enhancing soil fertility and improving resilience against drought advances, are already eating more nutritious food that is
security. It was made possible with the support of the and flooding. So, as climate change makes farming more difficult, this produced more efficiently than it was two decades ago,
African Academy of Sciences may be our best bet for food security, too. and this trend is set to continue.