Present and Future Challenges To Food Production
Twenty years ago the millenium development goals aimed to eradicate extreme poverty and hunger, however, while global hunger was reduced between the years 2000 and 2014, following 2014 food insecurity stopped falling and now is, once again, on the rise – particularly in the wake of COVID-19.
At the moment, the invasion of the Ukraine by Russia and the punitive sanctions upon Russia that have followed are drastically squeezing the food supply. This is both through:
- Directly reducing food exports
- Indirectly through reducing fertilizer and fuel exports
Ukraine accounts for 45-55%, and Russia 15-25%, of all globally exported sunflower seed oil. On the global market Ukraine additionally accounts for 10% of wheat, 15% of corn, and 13% of barley exports, while Russia accounts for 19% of global wheat exports
Beyond this, however, Russia and Belarus account for about one third of global Potash production – an important component of fertilizer. While Russia produces 17% of the global output of natural gas, which is the primary source of hydrogen for the industrial synthesis of nitrates. Hence, as a result of the war, there has been a significant reduction in the volumes of fertilizer produced globally in 2022 when compared to previous years, which has contributed to reduced crop production all across the globe.
If Ukraine and Russia somehow decided to kiss and make up tomorrow, this would partially improve global food security. However, the Russian invasion of Ukraine also overlapped:
- The worst drought in living memory in the U.S.
- Floods in Pakistan
In much of the world this year there have been severe droughts. Respondents to a U.S. survey conducted across the west, Southwest and central plains expected overall crop yields to be down by 38% due to the drought, in the U.K., harvests of potatoes, onions, sugar beet, apples and hops are expected to fall short by 10-50% in 2022 while, in the EU, harvests are forecast to be 16% down for grain maize, 15% down for soybeans and 12% down for sunflower seeds. In Pakistan there have been floods, rather than droughts, which have reduced their rice harvest by 15%.
And as the world continues to rapidly warm over the coming decades, climate scientists anticipate that more extreme weather events are only going to become more frequent. And it seems unlikely that this warming trend will reverse. After witnessing the devastating effect that a cut in natural gas supplies from Russia is wreaking on Europe’s heavy industry it seems likely that the lessons which many countries in Asia, and elsewhere, will take from Europe’s demise will be to increase the use of domestically mined coal to provide for the energy needs of their local populations.
But even if we stopped all current CO2 emissions, global temperatures would continue to rise for a further decade or so, this is because when you hold in more radiation (by changing the insulating characteristics of the atmosphere) it takes time for the net build up of radiation to form a new thermal equilibrium (in much the same way as there’s a time lag between putting the lid on an open pan of boiling water and observing a temperature rise). Beyond just thermal equilibrium, there may be some positive feedback effects that kick in once the temperature rises beyond a certain threshold. For example, if the arctic ice were to melt, leaving the arctic ocean ice-free, this would greatly accelerate global warming due to the reduced albedo (radiation absorption) of water relative to ice. The emission of methane (a potent greenhouse gas) trapped in melting permafrost or the emission of CO2 from massive forest fires would be other examples of positive feedback that may cause global warming to continue even in the absence of further CO2 emissions on the part of humanity.
Furthermore, even in the absence of temperature change, there are two further concerning factors which threaten to push standard agriculture into an irreversible decline:
- The rapid erosion of topsoil all over the world, due to modern farming practices
- Groundwater depletion
About 25% of irrigated agriculture globally relies on ground water. The Punjab in north India, is probably the most water stressed, highly productive area on earth with only 17 years supply of groundwater left, after which a lot of farmland there maybe reduced to dessert. However, many other productive agricultural areas, such as the central and West U.S., Morocco and Peru also face significant problems relating to groundwater depletion.
Soil erosion poses another threat to the productivity of standard agriculture. It is estimated that the soil erosion caused by existing farming practices are reducing global agricultural productivity by 0.3%/year. Changes to how we farm could prevent this but such changes are currently uneconomic and, for that reason, soil erosion continues apace with land degradation currently affecting 30% of the total land area of the world.
Fertilisers can compensate for soil erosion, but such fertilisers require hydrogen (which currently comes from natural gas), phosphate and Potassium. Global reserves of natural gas do seem to still be increasing, but all the major discoveries were made in the 60s and 70s. A shortage of phosphorous does not seem imminent as there are between 100 and 300 years of phosphates left while Potash is projected to peak in 2057. It’s worth mentioning that projection for peak non-energy resources are often unfounded as, once they get scarce the price skyrockets and it becomes economic to mine lower grade ores (an activity which is usually more energy intensive). Grade-tonnage curves are frequently such that the total tonnage of metal at an arbitrarily low grade, in a given mine, is often many times more than the tonnage that ends up getting mined due to the expense of mining the poorer grades and, globally, if you are willing to mine poorer grades you get more tonnage still as in addition to getting more tonnage out of existing mines, whole new deposits that otherwise would never be mined also become economic – the trade-off is more energy expended and more waste rock and tailings produced for a given extracted tonnage of product.
The exception to the principle of always being able to squeeze out more minerals by throwing more energy per unit mineral mined are the energy minerals themselves (oil, coal, gas): when the energy you expend extracting a given amount of fuel exceeds the usable energy obtained from burning that fuel, then there’s no point in mining the fuel in the first place. So there’s a hard physical cut off point when it comes to the minimum viable grade of energy minerals. Some studies conclude that the EROI of the oil and gas sector has plunged from 44:1 in the 1950s, to 15:1 in the year 2000 down to 8:1 today and project it will decline to 6.7:1 by 2040, exponentially increasing until the fossil fuel industry collapses, unable to produce any net energy for the rest of society. However, other studies have calculated a remarkably stable EROI, averaged over 30 companies, of 11:1 over a 20 year period. But even if the more optimistic study is correct and the fossil fuel industry will stably chug along without collapsing, increased soil erosion will still require increased fertiliser and increasingly active farm machinery, which will require more diesel and emit more CO2 for each unit of food produced. And keep in mind that agriculture, forestry and other land use already accounts for 24% of global green house gas emissions, a figure which will likely increase as more fertiliser gets applied to fields (and forests) to compensate for soil erosion.
The Decline of Standard Agriculture and Future Food Scarcity
Plant species often require a fairly narrow range of:
- Soil Quality/Nutrients
- Soil Moisture
- Soil acidity
- Conditions that won’t cause them to be ruined by pests and mould
- Sun
- Humidity
- Temperature
That varies in a specific way across the year to complete their life cycles and survive in a given location. If the desire is to maximise the edible yield of a plant then the optimal range of these variables becomes narrower still. When you consider all the climatic variables that need to be just right for agriculture to work on land, you can start to anticipate just how much havoc climate change could wreak on agricultural productivity.
The effect that warming temperatures will have on climatic variability is unclear with some papers suggesting a reduced variability while other papers anticipate increased extreme weather events as a result of climate change. But even shifting the combination of soil/rainfall/temperature in the absence of variability will still create a nightmare for farmers trying to work out what crops are most appropriate for their field (especially if they need new machinery to change crops). Higher CO2 will probably favour photosynthesis for some plant species and the effect of temperature on photosynthesis is complicated – up to a point higher temperatures cause the rate of photosynthesis to rapidly increase, but beyond a certain temperature threshold, higher temperatures tend to denature and damage the plant’s enzymes and, in turn, reduce its ability to photosynthesize.
Jon Feymann’s article Climate Stability and The Origin of Agriculture offers us a sobering conclusion: The last 10,000 years have been the most stable climatic period in all of human history. Climate instability is the rule; climate stability is the exception. He, furthermore, convincingly argues that the only reason agriculture could even develop in the first place was because of the unusually stable climatic conditions that prevailed over the past 10,000 years. If our climate should undergo a phase change back into the regime of high instability, that prevailed during the first 100,000+ years of our existence as a species, agriculture as we know it may no longer even be possible or, at the very least, crop yields will suffer terribly.
Groundwater aquifer depletion and soil erosion will add to the damage that uncertain climatic conditions will deal to crop yields. And on top of that, unless renewable energy (which still only accounts for 10% of primary energy production) can successfully replace fossil fuels in the coming decades, including hydrogen production to power heavy machinery, then when fossil fuel extraction peaks, we might even be faced with less energy available to compensate for the effect of climate change (through mining and applying more fertiliser, etc.,) soil erosion and groundwater depletion.
And on top of that, the world’s population is still growing so, if anything, we need to expand our agricultural production. Even keeping food production constant will not be enough in the face of a growing population.
So there are solid reasons to be concerned that the amount of food produced by our existing standard land-based agricultural system may be about to go into a terminal decline. Given the high levels of meat consumption and obesity, this decline may not immediately be critical, even in the face of an increasing population, but sooner or later, in the absence of additional sources of food production, a persistent decline in the existing food production system will result in mass starvation and all the social problems that accompany desperate starving people struggling for an essential, but dwindling, resource.
Could Seaweed Cultivation Be The Answer?
Given the main challenges of land agriculture are:
- Soil Erosion
- Groundwater depletion
- Climate instability
It should be pretty clear that seaweed has multiple advantages:
- It doesn’t need soil
- Saltwater in the ocean is constant and plentiful
- The high heat capacity of the sea buffers against variable air temperatures, cold/warm winds, sunshine variations, etc..
Places with continental climates tend to be located far away from the sea and be subject to severe temperature oscillations. Temperate climates, on the other hand, tend to be in regions closer to the sea and have more moderate variations in temperature. But under the sea itself is where the least variation in temperature occurs. So, if we’re concerned about climate variability, the ocean represents a vast oasis for food producers to take refuge from the extreme temperature oscillations that we may face in the future.
And, ofcourse, seaweed is unaffected by rainfall over the ocean as well, compared to land plants which require a delicate mix of rainfall, not so little that they dry out, yet not so much that their roots get water logged. While the changing rainfall patterns, that climate change may give rise to, could ruin land based harvests by pushing the plants beyond their acceptable range, seaweed will be unaffected. And while wildfires (which we may see more of) can can destroy fields of dry crops and orchards seaweed will also be completely unaffected.
At the end of the day, the main business of agriculture is the production of edible energy, to provide people with the energy they need for their bodies to conduct their important life-giving functions, like pumping blood and breathing air as well as the energy we need to conduct day to day activities like thinking and moving. Energy comes from the sun and edible energy production can be increased by increasing the area of the planet, which the sun illuminates, that is under cultivation.
Only 1/3 of the surface of planet Earth is land and, of that land, 38% is used for agriculture. (1/3 for crops, 2/3 for livestock grazing). 2/3 of the surface of planet earth is oceans and, although the surface layers in most parts of the ocean contain too little nutrients to support extensive seaweed growth, with the addition of appropriate nutrients into those surface layers, most of it could be used to grow seaweed.
An interesting technology that could simultaneously produce carbon-free electricity and bring nutrients from the deep layers of the ocean into the sunlit surface layer, making them suitable for the cultivation of seaweed, is OTEC, a technology that uses the temperature differential between the deep ocean and the surface ocean to generate CO2-free baseload electricity.
It will take time to develop seaweed cultivation to the point where it can realise its full potential to feed the world, but, to avoid disaster initially, we don’t need to cultivate all of the oceans at once, we merely need to increase the production of seaweed at a sufficiently high rate to compensate for any decline in standard, land-based agriculture that may result from climate change, soil erosion and groundwater depletion and the good news is, people like Richardo Radulovich are already working hard to develop suitable varieties of seaweed, locations and cultivation techniques to enable the oceans to yield a bountiful harvest to those who choose to cultivate them.
Conclusions
As human populations grow, our land is becoming increasingly crowded. 38% of it is already used in agriculture and there are questions as to whether we can mine enough minerals to continue to provide for the needs of this advanced and prosperous civilisation (and even if the minerals are there, would their extraction unduly disrupt the lives of farmers, indigenous peoples and other locals?). In the last few decades, public sentiment has become increasingly negative and many fear the possibility that climate change could catastrophically impact our food production systems and infrastructure through both extreme weather events and rising sea levels.
The ocean represents a vast hugely underutilized, underpopulated space. An almost empty area (compared to land) that accounts for the majority of the Earth’s surface. Out there on the high seas, lies the potential to grow all the food and mine all the minerals that are required to provide for an abundant and prosperous civilisation without interfering with the land rights of any indigenous peoples, or other local populations. A sea-based civilization that fully utilized the resources of the oceans could provide a prosperous life for all of the world’s people and facilitate the level of cooperation required to undertake further exponential technological development that may, someday, take us all the way to space.
Furthermore, a floating civilisation, need have little to fear from climate change as even relatively significant global temperature fluctuations, will likely have little impact on seaweed cultivation, while rising sea levels pose no threat to floating infrastructure.
So the question is: Would we prefer to stay on land, amid dwindling resources, deteriorating agricultural production, in land-based homes that will increasingly be ravaged by fires and floods as extreme weather events become more frequent, surrounded by steadily growing levels of poverty, starvation, desperation, anger and conflict?
Or would we rather sail towards a future of prosperity, security, abundance and hope out on the high seas?
John
