What global warming means

Climate change means a shifting in statistical averages.  In the case of global warming this means a shift to the warmer.  Mostly this affects areas situated closer to the poles.  Even if it on average gets wetter it is not so everywhere just because climate is global.  Some places suffer drought while others get floods.  This is due to the wind pattern being shifted to some extent, too.

To understand how this works one has to understand the concept of greenhouse effect.  The Earth gets it heat from the Sun and then radiates it out to space.  Some gases in the atmosphere can delay the radiating to space.  Nitrogen can’t do this and neither can oxygen and argon.  These three consists almost the entire of the Earth’s atmosphere.  So the strength of the greenhouse effect is determined by at most a few per mil of the atmosphere’s content.  Mostly this is about carbon dioxide, but also methane and laughing gas.  The effects of such gases are strengthened by water vapour.  In contrast there is a limit to how much water vapour air can contain.  Trying to exceed this limit instead makes it precipitate as dew.

Global warming is caused by the man-made increase in greenhouse effect.  Humanity releases larger amounts of different greenhouse gases than what nature can take care of.  These are accumulated in the atmosphere and retain more heat.  Then there are different mechanisms strengthening the effect of those.  Warmer air can contain more water than colder air can.  Moreover, the amount of surface covered in snow and ice decreases.  This makes the Earth on average darker which in turn strengthens the warmth.

Astronomical factors can’t explain us having global warming now.  There are at the moment no processes increasing the seasonal differences in the mid-latitudes of the northern hemisphere.  Such have for hundreds of thousands of years lead to a warmer climate.  The Sun has neither started to produce more energy.  On the opposite the amount of energy it emits has decreased somewhat.  As such the warming has to be explained by more warmth being retained.  Which means man-made increase in the greenhouse effect’s strength.

Since global warming is a matter of probability it is not obvious to everyone.  A small number still maintain that it would not exist.  One extreme weather event is then opposed to with the opposite extreme event.  Large forest fires are blamed on arsonists.  As if the probability of them happening would not be affected by drought.  This is in turn affected by global warming.

Some of this denial has to do with not having to deal with the problem.  Otherwise this is due to each year not being noticeably warmer than the previous one.  However, if it had been so quick society would have already collapsed.  Crops need a certain span of temperature and degree of moisture.  If the conditions are outside this span the harvests are destroyed.  Same applies to the plants eaten by free-rage animals.  Sweden did in fact get crop failure in the summer of 2018.  I have never experienced such at hot and at the same time dry summer.  (1992 was equally dry and 2010 equally hot.)  We managed without famine by importing food.  But what if the entire world had been affected in the same way?  Civilisation would have been on the brink of ruin.

Others seem to think global warming would be something good.  If the process had been slow this might have been sensible.  However, it now goes so fast it already cause problems.  This is not just about local drought or flood becoming more and more likely.  It also increases the likelihood of unhealthy heat-waves.  Organisms living in water can suffer heatstroke, too.  In addition, sea level rises when the world gets warmer.  Partly, water expands when the temperature rises.  Partly, glaciers on land melt and add more water.  This may lead to large areas of agricultural land being swallowed by the sea.

I don’t think it is possible to stop global warming.  Too much damage has already been done.  In contrast we have to slow it down so it does not go faster than we have time to adapt.  This is not about sudden total ban on loads of things people apprehend.  Instead this is about phasing out some types of technology.  Like for example power stations and engines running on fossil fuels.  Buildings have to be made more energy-efficient particularly in cooler areas.  Agriculture has to be converted to less meat production.  Moreover, artificial fertiliser has to be made using methane instead of oil.  Methane does not have to be extracted as a fossil fuel.  We could as well use biogas which is a by-product of composting.

The most important thing in this context is not losing hope.  If too many people gives up the necessary will not get done.  Predictions about possible apocalypse then becomes self-fulfilling prophesies.  But if one is not too suppressed by others one can in fact do something oneself.  Since 2005 I have gradually changed lifestyle to decrease my environmental impact.  I have drastically reduced my meat consumption, compost and recycle.  Having shopping for pastime I can’t afford anyhow.  Neither do I take a car particularly much, and have not flown since 2017.  If someone would offer me to invest in carbon capture and storage I would say yes to that.  This is the only form of carbon offset I think work in reality.

 

Uploaded on the 22nd of May 2024.