While we should normally expect climate variations detectable though the secular or even decadal averages, it is at the yearly scale that weather measurements confirm to humanity the extent of global warming. Each new year brings us a lot of telling figures that show us it is hotter than previous ones. In other words, evolution of a geological phenomenon is perceptible on a human scale since it is tangible for today’s generations. The fact that this acceleration is decoupled from the progression of CO² emissions raises the hypothesis of chain reactions initiated by the melting of ice and the reduction of albedo or the disappearance of vegetation cover (artificialisation of soils or disappearance of forests by both fires and overexploitation) that actually « air-condition » the atmosphere through transpiration. At same time, it confirms the depletion of damping phenomena such as the absorption of CO2 by the oceans or biomass. In other words, global warming is accelerating and regulatory loops are no longer operating.

Yesterday, the global warming was still a dilemma for climate-skeptics (now officially offside). Today’s main issue is the level of increase in temperature. While some people believe that a warming limit of + 1.5 ° C is still a possibility, the scientific community seems to agree that this threshold will be crossed in 2030. Until now suspected of having dramatized the situation, the IPCC (Intergovernmental Panel on Climate Change) itself recognizes today it has underestimated the rate of warming: the increase in the average temperature of the globe would rise from 7 ° C instead of 6 by the end of the century. In the public opinion, collapsologists have recently joined the debate. While southern Australia was facing heat stroke of + 50 ° C this winter, Americans were experiencing a cold snap with temperatures below -50 ° C. In Europe this summer, we got two extreme waves of heat, to discover afterwards that both July and October this year, have been the warmest on earth since the dawn of time. These actual facts show us clearly that today, we are no longer living in the same world as yesterday.

The agricultural sector differs from those of industry and services by its dependence on climate since among the main factors of production are the water resource, the temperature and the sunshine. This dependence is all the more important while crops grow in open field and their cycle is long. The impact of climate change on factors of production above is huge. The community of agronomists usually addresses this challenge from the perspective of global warming.

I guess one of the reasons we are addressing climate change from the perspective of warming is that the IPCC is focusing its approach on that. Probably because the warming is easier to study though models than the climate deregulation which is defined by brutal variations of the meteorology. The climate deregulation is on local and short term base, when warming is global and a long term phenomenon. Moreover, warming predictions are based on lot of historical data, while deregulation suffers from a lack of references related toits local character as well as the lack of footprint of past weather episodes. In other words, from the fact that what is poorly known doen’t exist, humanity perceives climate change through the prism of warming. In addition, as regards to climate change, the warming has become the measure of the phenomenon for the humanity which has set goals in this regard. For today’s digitalised civilization, which now only recognizes what is being measured, climate warming puts second-hand the issue of climate deregulation.

I think this is the main challenge facing the community of agronomists through climate change. At least in a very short term since an increase of around 6-7 ° C at end of the century will be extraordinary. For now, occurrence in a mess of cold or heat, torrential rainfalls or other violent gusts of wind, isn’t certainly compatible with life that has adapted for millions of years – through Darwinism – to the sequence of ordinary meteorological events that occur each year in a predictable order. This is particularly true for flowering plants that dominate flora after appearing late in evolution: each stage of their reproductive cycle is under dependance of a narrow meteorological « shooting window ». Species and their ecosystems, whether natural or cultivated, are clearly threatened by climate disturbance. Intensive monoculture is no more immune to this reality than the ecosystems of organic farming that some claim is resilient: it sounds logical that the lethal nature of certain extreme weather phenomena threatens these artificial ecosystems by suppressing certain species that contribute to their functional balance.

Therefore, facing the threat of climate change, the community of agronomists will have to find out other models than those it had imagined in the last century to increase yield and quality of harvests. In response to the increase in average temperatures, some say crops should simply be moved north or upstream of the crop calendar. I think that a relocation of crops in time or in space, as a response to the rise in temperatures, is a stalemate, as far as there is no lattitude or period in the year, susceptible to be preserved from weather disturbance.

I have some doubts about the forecasts made by certain world organizations that claim that with intensive monoculture or organic farming, the planet could feed tomorrow 10 billion people, under the only conditions to abandon on the one hand the meat diet, on the other hand to solve the problem of waste which today accounts for one-third of harvests. I am afraid that overabundance of food raw materials that we have known since the second world war within our temperates regions, will soon appear only as a fleeting golden age. We no longer live in the same world as yesterday, and the amplification of the weather disruption we are already noticing, undeniably calls for ttally different answers that those that have been proven in the past. This disruption is logically I guess, the consequence of increasing imbalances between physical characteristics of different parts of the globe. This is for sure about to increase with a warming which upsets the distribution of the quantities of energy stored on both the surface of the continents and the masses of either free or frozen water.