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Dear Readers, Rising CO2 levels in the atmosphere has undeniably had a warming impact on the Earth's climate, with the planet as a whole having a mean temperature during 2020 just over 1.0C above pre-industrial averages. The warming impact has undeniably been greater in recent years in Russia, Canada, and northern Europe where- in the winter months the mean warming has been over 2.0C above pre-industrial averages for the season. Some of this warming may be related to the Earth coming out of the Little Ice Age- but some of the effect is undoubtedly due to CO2 levels since we are entering a period of quiet Sun (weaker sunspot cycles with slightly weaker Solar output) which, all else being equal ought to bring a cooling back to the conditions of the 19th Century: Plainly that is not the case. But why do middle latitudes and higher latitudes in winter warm more? The exception is interior Antarctica that has got colder in recent winters, and winter 2021 (June-August) was one of the coldest on record at the South Pole. The Antarctic Ozone Hole in the Antarctic stratosphere has also made a bit of a come-back in 2021 (during the Southern winter). Is that also in some way related to warmer, wetter winters in most middle and high latitude areas? The answer is a definitive "Yes". Most meteorologists appreciate the impact of something called the Law of Conservation of Angular Momentum on the Earth's global weather-pattern: In layman's terms, the Earth's rotation and the virtual absence of outside forces (gravitational tidal influences from the Sun and Moon, the effects of meteorites and bursts of super-charged plasma from the Sun following coronal mass ejections are largely negligible over just a few years) means that the atmosphere as a whole has to rotate with the Earth. From this, the frictional and pressure impacts of Easterlies at low latitudes and near the poles are counterbalanced by the frictional and pressure impacts of Westerlies in middle latitudes. This applies to both the Northern Hemisphere and the Southern Hemisphere and largely dictate the existence of the Westerlies in higher latitudes, but not necessarily where they occur or how strong they are. However, global weather- patterns are also (and primarily) controlled by the heat input to the Earth-Atmosphere system, how much heat there is and where it is on the Earth. It is also dependent on moisture and atmospheric temperature gradients. A warmer Earth not only means more moisture in the atmosphere but, with the edges of polar ice-caps (seasonal and year-round) retreated polewards it means that the Westerlies- intensified and largely fixed by atmospheric and near- surface temperature gradients (what meteorologists call baroclinicity) as the depressions that drive these depressions also need these zones of baroclinicity. Now, the areas of the Earth where easterlies are at the surface are called sources of Westerly Atmospheric Angular Momentum (AAM) or simply Global Atmospheric Angular Momentum (GLAAM). This arises because Easterly winds, blowing in a direction opposite to the Earth's rotation result in the Earth losing a bit of it's eastwards rotation to the atmosphere- in other words these areas with surface Easterly winds are sources of Westerly AAM (or GLAAM). Since, at least under current climatic conditions, the winds aloft do not start blowing 1,000's of miles an hour from the West and remain fairly constant in speed at the height of the winter (seldom more than 200 mph at 10,000 metres' elevation) it follows that other areas are sinks for Westerly AAM (or GLAAM). These areas are in higher latitudes where often -strong Westerly winds blowing over the sea or against hills result in a frictional force at the surface slowing the Westerlies down- and helping to speed the Earth's rotation up. The fact that the Length of Day remains fairly constant throughout the year- and from year to year (though the Length of Day is very slowly increasing by a millisecond a decade mainly due to the effects of marine tidal friction due to the Moon)- means that Westerly AAM is imparted to the rotating Earth as much as it is removed via tropical and Polar Easterlies. Now, for some interesting observations of global weather maps by a seasoned meteorologist (myself): For almost all the year the Westerlies seem to be concentrated at the highest latitude 40% of the Earth's surface (sin-1(1-0.4)=36.9 degrees, so that is Westerlies restricted to North of 36.9 degrees North and South of 36.9 degrees South). Of course, there still are some occasions with Westerlies in lower latitudes, strong Westerlies occur on the equatorwide of hurricanes and tropical depressions when these occur but these are counterbalanced by just as strong violent easterlies on the other side of these tropical storms. South-Westerlies blow over India and adjacent parts of southern Asia during the Summer Monsoon- which will help reduce some of the need for strong Westerlies at higher latitudes of the Southern Hemisphere in the winter there, so this will not help weaken Westerlies in high Northern latitudes. Often the Tibetan Plateau gets Westerly winds in winter, but these have seldom been strong and they are restricted to those areas north of 30 degrees North. (Continued below)