The forest is burning in Australia. The fire wins of the houses that their inhabitants do not get to save and a lot, to survive, to flee, abandoning to the flames, their property and memories of a lifetime. Animals die, up to a billion and a half, we read. Of large cities, including the capital Canberra, are drowned in a cloud of smoke, making the air unbreathable so that the heat records are beaten. Spectacular pictures show how the fire fighters fought with poor weapons against the flames, due to lack of water bomber. Stories tell of how are saved a few marsupials, thanks to the careful attention of the people at heart and that, through social networks, collecting hundreds of thousands of dollars around the world.
To go further on this topic, read also : Australia: slugs giant survived the fires
The Prime minister of australia, Scott Morrison, comes back late from a vacation to Hawaii and is pilloried in the media world. It must be said that he has never been particularly sensitive to the theses of the Ipcc, even if they open up, paradoxically, a new market for its coal industry. In fact, if japanese cars propelled by hydrogen engines liquid circulating in the streets of Tokyo, it is that their fuel could be manufactured thanks to the energy of the coal power plants australian !
the napoleonic era, the arsonists were passed by the weapons
forest on fire appear in January on the screens. The emotion is global, because these images are spectacular and terrifying. The fear of fire is universal, and, in France, the incendiary trial in assisi are the most often convicted by juries to the maximum penalty ! At the time of napoleon, they were passed by the weapons and the prefects of the departments affected were replaced if the forest fires were frequent on their territory !
Read also Fires in Australia : the urgency to get out of the logical partisan
For a century, the earth's temperature has increased by an average of 1 °C. It would appear that extreme weather events are becoming more frequent and this would be why the forest burns, it is said. If it is not forbidden to think that global warming plays a role in the recent fires, it may not be that minor. In fact, it should not be confused with the phenomena of weather and climate phenomena, because, if they play over a long period (1 °C in a century), this secular variation is much less than the daily fluctuations of temperature. In France, between the day and the night, the temperature varies by an average of 6 to 10 °C. The world record for variations on the same day is 55.5 °C. It has been recorded in the city of Browning, Montana (USA) ; the amplitude maximum annual between summer and winter in the same place, she returned to Verkhoïansk in Siberia with 104,4 °C. For those who remain less convinced by these reminders, it is enough to recall the dates of other major fires. Thus, in 1974-1975, a period when it was feared that the globe cools, 117 million hectares went up in smoke in Australia, almost seven times more than the recent fires in 2019-2020 (16.8 million hectares) and almost two times the total surface of France (64.6 million acres). Of course, all this is not to say that these fires are innocuous or that the position of the current australian government is defensible, and even more so that this country lacks neither the sun, nor wind, nor of uranium, of which it owns 23 % of global reserves, to design an energy system that would limit releases of greenhouse gases.
The civilization of the aboriginal practice since 40 000 years ago the burning
The frequency and importance of fires depend on the seasons, of man and of the manner in which the forest is or is not managed. In Australia, the fires are reported from December to march south of the continent, and from July to October in the north. An accurate record of these gigantic fires of vegetation is required since 1851, and the Australians referred to them in speaking familiarly of the " black Thursday ", of "Tuesday," red ", of "black Christmas," or " ash Wednesday ". If it happens that the fires are caused by lightning, the fire is often lit by the man : so many homes do not start simultaneously by chance at the same time, especially when there is no storm.
The fire is as old as civilization aborigine who, like all the civilizations to be primitive, since 40 000 years, practice the clearings, in other words : the slash-and-burn traditionally limited to the part herb to the ashes fatten the grass to sprout with the next rain. In addition, certain plants, and to regenerate, need the fire. What happened to that, a few weeks ago, in both sites, the fire would spread to the forest and destroy ecosystems which, in the best cases, will take decades to find their balance past ? The dryness of the air and the extreme temperatures have certainly played a role, but the key is in the management of the forest, in the creation of the firewall, in the delegation given to the aborigines to launch counter-fire. For example, in France, a strict policy reduces the extent of the fires in the Landes region, such as around the mediterranean basin through the monitoring of the firefighters, the démaquisage, the advancement of the protective, to the fleet of water bombers and retardants, and the prohibition of the walks in the forest days of great drought.
These fires are also an opportunity to remember that forest fires do not impact on the oxygen that we breathe. Thus, the president of the Republic, Emmanuel Macron, has said it was wrong to declare the August 22, 2019 : "Our house is burning. Literally. The Amazon, the lungs of our planet, which produces 20 % of our oxygen, is on fire. This is an international crisis. Members of the G7, see you in two days to talk about this emergency. "
It is unfortunate defending good causes with bad arguments
The Amazon does not produce 20 % of Earth's oxygen and, if the terrible fires of the summer of 2019, have an ecological impact is real, because they destroy the ecosystems and their biodiversity, the rate of oxygen of the air has not been modified ; it is 21 %, a rate stable for millions of years, and will remain so.
To go further, also read the Threat on tropical forest
If a wood fire gives off a strong heat be immediate, the quantity of heat emitted is the same as if the wood had decomposed slowly in the forest, of course it happens slowly and goes unnoticed. When the organic matter putréfie to form humus or compost, one observes a release of heat ; the fires of the Amazon emit the same heat as if the entire forest had rotted on the spot. The decomposition is done by a fire or under the direct influence of bacteria, as it passes by the push of mushrooms, or food to scavengers, there is overall conservation of energy and matter, even if it is not in the same amount of time. The energy of the sun fuels the photosynthesis and thus produced with carbon dioxide the complex molecules of the living world. The chemistry of life is the chemistry of carbon. The laws of thermodynamics indicate that, in this process, energy is conserved. Thus, the cycle of living matter on the Planet keeps the full rate of the oxygen of the air, 21 %, the rate of CO2 from the air (0,04 %) and the energy of the sun used in photosynthesis.
If today, there is an increase in the rate of CO2 in the air, it comes from a part of the combustion of fossil fuels (coal, lignite, oil, gas, peat...) and the liberation of the carbon dioxide dissolved in the oceans. The temporary peaks of forest fires do not play any significant role.
These fires are not doomed to be
It is regrettable to defending good causes with bad arguments. The forest fires in Australia have to do with the management of the forest and the relationship between the State, the aborigines and the great farmers of this continent depopulated. The revival fires of the amazon rain forest has its origin in the policy of the president Bolsonaro. These fires are not inevitable, as well, Martine Droulers, geographer of Brazil, recalled in August of 2019 that" [it] twenty years ago, there was a lot more fires than today. Twenty thousand square kilometres [two million ha] burned, on average, every year. The trend was however declining in the past ten years, the number of fires increases again in the last two years. The fires that ravage the Amazon today are an alert that calls to vigilance, but it is important to remember that these fires are anything but new, and that many of them are cleaning areas that have been deforested ".
The warming of the planet is not the only cause, or even always the primary cause, of the evolution of ecosystems, the claim led in particular to not deal with the relations of man and the forest always local and specific. The forest burns because in the vast majority of cases men have turned on the lights.