Planet Earth Recorded Its Shortest Day
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Planet Earth Recorded Its Shortest Day


Earth is Spinning Faster: A study published in Geophysical Research Letters of the American Geophysical Union suggests that global warming has led to significant melting of glaciers due to which our planet’s axis of rotation has been moving faster since the 1990s.Earth takes exactly 24 hours to rotate once on its axis. Classic textbook knowledge, right? Well, not anymore. The reality is constantly changing and so are the facts. On July 29, Earth recorded the shortest day, thus establishing the fact that it is spinning faster than its usual speed. The planet completed a full spin in 1.59 milliseconds less than its standard 24-hour rotation. It is interesting to note that this is not the first time that the Earth has quickened its pace. According to a few media reports, Earth recorded its shortest month in the year 2020 and July 19 was recorded to be the shortest day of that year.


Reports suggest that July 19, 2020 is to date the shortest day in history as it took the Earth 1.47 milliseconds shorter than usual to complete one spin. A study published in Geophysical Research Letters of the American Geophysical Union suggests that global warming has led to significant melting of glaciers due to which our planet’s axis of rotation has been moving faster since the 1990s.


Climate change has also caused the north pole to shift in the eastward direction since the 1990s. This is happening due to changes in the hydrosphere (hydrosphere is the total amount of water on Earth). As per the study, the satellite data from NASA’s Gravity Recovery and Climate Experiment (GRACE) mission calculated that the average speed of drift was 17 times faster than from 1981 to 1995. Also, in the last four decades, the poles moved by about 4 meters in distance. According to a report in the Independent, if the Earth continues to rotate at a faster pace, it could lead to the introduction of negative leap seconds. The purpose of introducing these negative leap seconds would be to keep the rate at which the Earth orbits around the Sun consistent with measurements from atomic clocks. This could potentially create a wounding effect for IT systems and software and GPS satellites relying on the clock.


The rotation of the Earth has no real effect on losing the atmosphere into space. Individual atoms of the lighter elements in the air are lost when they get heated to the point where they can, effectively, evaporate into space; however, this manifests as high kinetic energy, allowing the atom to escape Earth’s gravity. The heavier elements, like nitrogen and oxygen, rarely leave. It’s mostly hydrogen and helium. Any loss of atmosphere is going to be due to rising temperatures. That causes the atmosphere to expand so much that it is further from the Earth, and for the average velocity of air molecules to increase, which will put more of them over the escape velocity of the Earth. This is how Mars lost its atmosphere. The main cause is human emissions of carbon dioxide, methane, nitrous oxide and other “greenhouse gases.”

These gases, when emitted into the atmosphere, absorb the heat radiation given off by the Earth’s surface, and redirect some of it downward.


This process is responsible for essentially ALL of the warming the Earth has seen since about 1970, now 1.0 Celsius (1.8 Fahrenheit).

As individuals, we can structure our lives so as to emit less of these gasses, especially CO2. (CO2 emissions come from driving a car, using electricity if your utility burns coal or natural gas, flying, food production, and more.) Americans, in particular, create a lot of CO2.

But to be realistic, there is very little we can do as individuals to reduce global warming from greenhouse gasses. Our only hope is to change the energy and transportation infrastructure of our society — for us to drive electric cars powered by clean energy sources like wind, solar, nuclear and hydropower. We must advocate for clean energy production at all levels — energy that doesn’t emit greenhouse gasses — and especially vote in representatives who recognize the threat of global warming and will do something about it at the state and national level.


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