Super fact – Page 12

Global Warming is Happening and is Caused by us

Superfact 25: Global warming is happening. Or if you call it Climate Change or Climate Disruption is happening. And it is happening very fast. We also know that it is caused by us primarily as a result of our burning of fossil fuels. There is a long-standing scientific consensus on these two facts because the evidence is conclusive. Check the evidence below.

This is a long post. However, I summarized this somewhat complex issue in a post I hope is both comprehensive and easy to read at the same time. I believe you can learn a lot from reading it. Note in this post, Global Warming Is Happening And Is Caused By Us, I will use the terms climate change, climate disruption and global warming interchangeably, or nearly interchangeably. I am doing that on purpose.

A lot of people would like to dispute this fact. Including large segments of the public, politicians, and political organizations. I was once a so-called skeptic myself. However, climate scientists very rarely dispute this because of the large amount of compelling evidence. This is a good summary from NASA. We know it’s true, it is important, yet disputed, which makes it a super fact in my opinion.

Below I created a top 10 list of evidence for the fact that climate change / global warming is happening. As well as a top 10 list of evidence for the fact that we are the cause for it. Primarily because of our burning of fossil fuels.

Evidence that Global Warning is Happening

(1) The temperature records collected by numerous organizations show that global warming is happening. Organizations such as NASA, NOAA, the Hadley Centre, the European Centre for Medium-Range Weather Forecasts, the Japanese Meteorological Agency, the World Meteorological Organization, and many more, use data from land-based weather stations, ocean buoys, satellite measurements, and other sources to monitor Earth’s climate. Comparison with the palaeoclimatological record shows that the rise in average global temperatures is extremely fast. This is the smoking gun. However, for those who question the data from all of these organizations there are other simpler types of evidence (see below).
(2) Global sea levels has increased by 20–25 cm (8–10 in) since 1900, with half of that increase occurring since 1980. Sea level rise occurs from a combination of thermal expansion and the melting of land ice, both which happen as a result of warming. This sea level rise has been the fastest in “at least the last 3000 years”.
(3) Arctic ice is melting. See the video from NASA below.
(4) Glaciers are retreating.
(5) The Antarctic ice sheet is losing ice at a rate of about 100–200 billion tons per year, which has increased in the past two decades.
(6) Eco zones are generally shifting northward and to higher elevations, meaning that plant and animal habitats are moving towards cooler regions as temperatures rise in previously suitable areas.
(7) Snow seasons are getting shorter
(8) Extreme events are increasing in frequency showing that climate is changing
(9) After extensive research and scientific debates in the past there is now a long-standing scientific consensus that Global Warming is happening. This is not physical evidence itself, but it does not an appeal to authority fallacy either. Think about it in terms of probability.
(10) Old guys originating from northern climates like me, have noticed that the seasons are changing. Even if you dismiss all the evidence from NASA, NOAA, IPCC, and all the world’s meteorological institutions, and you claim that all the world’s climate scientists are all in a massive conspiracy, you cannot convince me of something that is contrary to what I can see with my own eyes.

Graphs and Videos Showing Global Warming

To see the NASA web page from where the YouTube video of the shrinking arctic ice is taken click here .

Graph showing global temperature rise since 1850 to 2022. There are five nearly identical graphs shown in different colors. Temperature anomaly graphs from NASA GISS – orange. HadCRUT – green. NOAA – purple, Japan Meteorological Agency – blue, Berkley Earth – red. The jagged curves show more than a 1.2 degrees Celsius increase | Global Warming is Happening and is Caused by us — Temperature anomaly graphs from NASA, Hedley Center, Japan Meteorological Agency, NOAA, and Berkley. Wikimedia commons << https://creativecommons.org/licenses/by-sa/4.0/deed.en>>.

Hockey stick curve going back 1,000 years. The recent uptick in global temperature is very sharp and very sudden | Global Warming is Happening and is Caused by us — The so-called hockey stick curve depicting the last 1,000 years. The blue line is the first hockey stick curve ever created (by Michael Mann). He used proxy measurements such as tree rings, green-dots 30-year average, red temperature measurements. Wikimedia commons <<https://creativecommons.org/licenses/by-sa/4.0/deed.en>>. This graph is taken from this page

The graph shows wild swings over the last 150,000 years and then a very sharp uptick at the end | Global Warming is Happening and is Caused by us — Temperature record for the last 150,000 years. Notice the sharp uptick towards the end. This picture is taken from this article.

Confusion About Climate Change

Before continuing I would like to address a couple of issues that sometimes trip up people. And prevent them from learning about this topic.

The question “climate has always been changing, why would we be the cause now?”, is a good question. If asked honestly. However, it is a bad question if it is asked like a gotcha or a dismissive statement. In this case it is a bad question. Because the paleoclimatologists and the climate scientists, in other words the experts on past climate, are the ones telling us that the current climate change / global warming is caused by us, it is not “natural”. They obviously say that because they know something that the dismissive laymen don’t. All everyone needs is a tiny bit of reflection to realize that you’ve got something to learn from them.

Sometimes you come across people who have a hangup over the fact that we use a few different terms interchangeably, global warming, climate change, climate disruption, inadvertent climate modification, etc. The people who have a hangup about this jump to the incorrect conclusion that there is some sort of deception or backtrack going on. If I talk about my dog and my mini-Australian Shepherd, I am not confused or deceptive or backtracking anything. It is the same family member. Whether you call it global warming or climate change or something else is a distracting non-issue, a red herring if you will.

To add some information about it. Climate change has become the more popular term recently, but the terms climate change and inadvertent climate modification predates the term global warming, which became popular in the 1980’s largely because climate scientist James Hansen likes to use it. Climate change is a broader term since it could include global warming and global cooling, but in the current context, global warming is a good term as well since that is what is happening now.

One advantage of the term climate change is that the average warming trend is in itself not the major issue. The effects on the overall climate that warming has is the more important issue. You could say that you want some global warming when the weather is cold and it would make sense. But you don’t want the destruction of eco systems, oceanic and atmospheric circulation changes, sea level rise, worse storms, draughts, floods, wildfires, etc., that it causes.

Natural Causes of Climate Change

There are many different kinds of natural causes of climate change. Two billion years ago cyanobacteria developed a form of photosynthesis that absorbed carbon dioxide and emitted oxygen, as well as a way of extracting nitrogen using a process called nitrogen fixation. This made cyanobacteria extremely successful. One consequence of this was that the carbon dioxide was largely removed from the atmosphere, and the earth got very cold, but the oxygen that was now present in the atmosphere paved the way for the existence of multicellular life and animals. To find out more about this, read this book.

The planet changed but it took millions of years. The emergence of land plants did something similar. Examples of other slow-moving drivers of climate change are continental drift and the fact that the light from the sun has gotten 6% stronger over the last one billion years (0.006% per million years).

Green algae sludge in water. — Cyanobacteria caused a global cooling two billion years ago while paving the way for the existence of multicellular life and animals. Stock Photo ID: 2197045895 by Andre Engelhardt.

65 million years ago an asteroid struck earth, which caused earth’s climate to change, which is probably what killed the non-avian dinosaurs. Another example of a past climate change driver is unusual volcanic activity. Volcanoes emit greenhouse gases, such as carbon dioxide (CO₂) and water vapor, during eruptions.

However, their contribution to the total CO₂ emissions in modern times is very small compared to human activities. Annual volcanic CO₂ emissions are estimated to be around 200-500 million tons while humans add 37-40 billion tons, or 100 times as much. Therefore, it is unlikely that volcanoes contribute much to the current warming, but the fine sulfate aerosols emitted by volcanoes can cause a significant cooling effect for a few years.

Two carnivorous dinosaurs and a flaming hot asteroid crashing through the atmosphere in the background. — Dinosaur and asteroids during extinction day Stock Illustration ID: 1438260563 by serpeblu

A black and orange colorful illustration of an erupting volcano. — Volcano – An active volcano that erupts lava. Stock Illustration ID: 2497156167 by MERT1995

One type of important type of climate forcing that’s been the cause behind the multiple ice ages that we’ve had over the last two million years are earth’s orbital cycles, or the Milankovitch cycles. There are three of them, orbital eccentricity, change in axial tilt, and axial precession. Could they explain the current warming? No, they can’t because we are currently in a cycle that should be cooling the planet. And it was until now. Below I have included a video from PBS that explains these orbital cycles.

Three illustrated orbital cycles. On the left orbital eccentricity, in the middle is the axial tilt and on the right axial precession | Global Warming is Happening and is Caused by us — Illustration of Milankovitch cycles from MIT’s Climate Primer.<< Link-22>>.

From PBS explanation and overview of earth’s three orbital cycles.

There are also short-term solar irradiance cycles. There is an 11-year cycle and an 80-year cycle, but these correspond to small changes. The 11-year cycle corresponds to a temperature change of 0.05 degrees Celsius.

In addition, the Sun’s irradiance has been slightly decreasing over the past few decades. Changes in the sun’s irradiance cannot explain the sharp warming we are witnessing. As you’ve seen above, neither can volcanic activity nor any known orbital cycles, slow moving climate drivers such as continental drift cannot explain it and we did not get hit by an asteroid recently. However, what fits the bill almost perfectly is our greenhouse gas emissions.

This is a brief overview from MIT.

What Does Climate Models Say About Climate Change

Unlike weather, the climate is not particularly sensitive to initial conditions (chaos). For example, we can be pretty certain that July will be warmer than January in Minnesota. We use climate models to try to predict future climate. All climate models rely on the laws of thermodynamics. But they vary in regard to the different understandings of the best ways to incorporate those laws in a representation of all of Earth. They do not come up with identical results. But they all get the average temperature of each region of the world right.

In addition, the various old climate models from the 1990’s do a very good job of what has happened during the last 30 years. They aren’t perfect but they are useful and more importantly for our context they serve as powerful evidence that the current warming is caused by our emissions. You remove our emissions from the models and none of what we measure will happen. Climate models are therefore the smoking gun with respect to what is causing global warming, just like the temperature record is for the fact that it is happening in the first place.

Unfortunately, the climate models have been maligned and misrepresented by those who wish that the public do not pay attention to them. That’s why we need to mention additional types of evidence (see below).

Evidence that Global Warming is Caused by US

(1) Climate models – as we have seen above, climate models are the smoking gun evidence that we humans are causing global warming / climate change. In addition, both simplistic and complex climate models show that 100% of global warming is caused by humans.
(2) Greenhouse gases will make the planet warmer, and we are emitting a lot of them.
(3) The upper troposphere is cooling, which shows that the heating is from greenhouse gases and not the sun or orbital cycles. To understand how the lower atmosphere is warming while the upper is cooling, think of the greenhouse gases as a blanket.
(4) winters and nights are generally warming faster than other seasons and times of day due to the increased presence of greenhouse gases in the atmosphere, which trap heat more effectively during colder periods. This is considered a key indicator of human-induced climate change.
(5) The speed of the warming, 0.31 degrees Fahrenheit per decade, or 0.17 degrees Celsius per decade is extremely fast. Known natural climate forcing tends to be slower.
(6) Human activities is the only known explanation for the current global warming. One way that we know that the current warming is caused by human activity is because we are currently in a cycle that should be cooling the planet. The same is true for the sun’s irradiance. It is not volcanoes or any other known cause. See the section above called “Natural Causes of Climate Change”.
(7) Isotope studies show that the origin of the greenhouse gases added to the atmosphere are from burning fossil fuels. This is referred to as the isotopic footprint.
(8) The observed temperature rise mirrors industrialization.
(9) More than 90% of excess heat from global warming is absorbed by the oceans, causing significant increases in ocean temperatures. Oceans absorb about a quarter of human CO₂ emissions, leading to lower pH levels. This is unprecedented in at least 26,000 years and is directly linked to anthropogenic CO₂. These effects have been carefully studied and observed.
(10) Nearly all actively publishing climate scientists say humans are causing climate change. This is not physical evidence itself, but it does not appeal to authority fallacy either. Think about it in terms of probability.

This is a short one-minute overview of the causes behind global warming that is happening.

This video from NASA is a bit longer, 13 minutes. Click here to see the page this is coming from

Graph showing possible causes for the observed temperature (blue), natural causes (volcanic, solar), human and natural causes (volcanic, solar, greenhouse gases, NO2, ozone depletion). — Natural causes for global warming / climate change would have cooled the planet, not warm it. Click here to visit this NASA web page regarding the causes behind global warming.<<Link-31>>

The Keeling curve starting in 1958 ending in 2022 showing the increase in carbon dioxide in the atmosphere. — The carbon dioxide concentration measurements began in 1958 at the Mauna Loa Observatory on the island of Hawaii. Since then, several other ways of measuring carbon dioxide concentration have been added.

Curve showing CO2 concentration starting 10,000 years ago. Again a very sharp uptick towards end. — From Scripps institute. Keep two things in mind. First the warming from CO2 is delayed and may result in positive feedback that can manifest decades and centuries later. Secondly, human civilization developed during a period of stable climate. That CO2 levels and temperatures were higher millions of years ago is not much comfort.

Graph showing CO2 concentrations starting 800,000 years ago. The curve is wavy until it suddenly shoots up towards the end | Global Warming is Happening and is Caused by us — Going back 800,000 years. From Scripps institute.

six young women and two young men holding signs. They are protesting Global Warming. — A Global Warming protest. It’s their future. Stock Photo ID: 1427361263 by manpeppe

To see the other Super Facts click here

Smallpox Killed 300 million People in the Last Century Before Eradication

Superfact 24: Smallpox killed 300 million people in the 20^th century. However, there have been no naturally occurring cases of smallpox since 1977, and the world was declared free of smallpox on May 8, 1980, by the 33rd World Health Assembly.

Vial with smallpox vaccine and syringe against blurred doctor's face. 3D rendering | Smallpox Killed 300 million People in the Last Century Before Eradication — Smallpox vaccine Stock Illustration ID: 1782022109 by Novikov Aleksey

300 million people is an astonishing number. It is six times the 50 million people who died from the Spanish flu. It is about four times as many people as the 70 to 85 million people who died in World War II. It is close to the entire current population of the United States. That’s how many people died from this very dangerous disease. It was eradicated by a vaccination campaign.

I think this fact qualify as a super-fact, first of all because of the astonishingly huge number of deaths but also for the fact that it is gone. It is hard to believe that this happened. It is hard to believe that the world has changed so drastically for the better. It is a shocking but true fact. Thanks to the vaccination campaign we are living in a much better world.

The picture is a world map showing countries in different colors. The colors indicated when smallpox was eradicated in that country. Dark blue indicates that it was before 1900 and that is Sweden and Norway. Light beige indicates it was eradicated in the 1940’s, which is true for the United States. Dark brown indicates that it was eradicated in the 1970’s and that represents, for example, India, Brazil and many African countries | Smallpox Killed 300 million People in the Last Century Before Eradication — This world map shows when smallpox was eradicated from different countries. The source is Our World in Data, originally Fenner et al. at CDC.

What is Smallpox?

Smallpox is an infectious disease caused by the variola virus<<Link-1>>. The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) certified the global eradication of the disease in 1980. The disease begins with fever and vomiting followed by the formation of ulcers in the mouth and a skin rash that later turns into fluid filled blisters with a dent in the middle. These blisters get scabbed and leave scars. The death rate was about 30%.

A child with covered by severe blisters. — Child with smallpox in Bangladesh 1975. Wikimedia commons photo by CDC/James Hicks.

The Eradication of Smallpox and Vaccines

The smallpox vaccine has a long history that begin in China where smallpox inoculation had existed long before it did in Europe. In 1796 the English physician Edward Jenner demonstrated the effectiveness of cowpox to protect humans from smallpox. Soon after several countries enacted mandatory vaccinations.

In 1807, Bavaria became the first country in the world to introduce compulsory vaccinations. In 1958 the World Health Assembly was called upon to eradicate smallpox. At this point 2 million people still died from smallpox every year. In 1967 the World Health Organization intensified the global smallpox eradication. As mentioned, smallpox was eradicated at the end of the 1970’s.

In 1998 & 2002 vaccination was dealt a blow by the Wakefield studies claiming that the MMR vaccine caused autism. Even though the studies were debunked, and several later studies showed no link between the MMR vaccines and autism, the fear of vaccines began to spread.

For example, in 2024 the American Veterinary Medical Association reported 37% of the dog owners surveyed believe canine vaccination could cause autism in their dogs. Not only is there no link between vaccines and autism, but technically speaking, dogs cannot be autistic as the condition is unique to humans. Unfortunately, the unnecessary fear of vaccines causing autism seems to only be getting worse.

To see the other Super Facts click here

Are you vaccinated against smallpox?

GPS uses relativity for accuracy

Superfact 23: GPS uses relativity for accuracy. Global Positioning Systems or GPS uses Special Relativity and General Relativity to guide you to your destination. In fact, GPS systems would be rendered useless without the Theories of Relativity.

Businessman finger pin for location points and search addresses on the world map application. Marking destination for travel or finding business places in GPS Satellite coordinates system online web | GPS uses relativity for accuracy — Stock Photo ID: 2502019165 by mayam_studio

Did you use Einstein’s Theories of Relativity to get to the grocery store today?

The theories of relativity may seem strange and impractical, something you only use for astrophysics, black holes, cosmology and extreme velocities. They feature strange concepts such as time dilation, the stretching and bending of space, events simultaneous to some are not to others, the universal constancy of the speed of light in vacuum, the energy and mass equivalency, etc.

Therefore, it is a bit surprising that without the theories of relativity the GPS app on your phone would not be able to guide you to the grocery store. That’s why I call it a super fact that GPS uses relativity for accuracy.

Space satellite orbiting the Earth. 3D rendering — Stock Illustration ID: 1372134458 by Boris Rabtsevich

GPS and Time Dilation

GPS is a satellite-based radio navigation system that provides location information and time anywhere on Earth. It is amazingly accurate. The basic GPS service provides users with approximately 7.0-meter accuracy, 95% of the time, anywhere on or near the surface of the earth.

The fact that the information is provided by satellites that orbit earth at high speeds and high above earth’s surface makes General Relativity and Special Relativity necessary. The GPS system needs to calculate precisely the time it takes for signals to travel from the satellites to a receiver on Earth for it to work. GPS satellites travel at high speeds causing a large enough time dilation that must be accounted for. In addition, they orbit earth high above earth’s surface where earth’s gravitational field is weaker than on earth’s surface. Clocks run faster in weaker gravitational fields due to gravitational time dilation, so you must correct that as well.

If you ignore relativity, you will accumulate a discrepancy of six miles in one day. You are not going to find the grocery store that way, unless you use the old-fashioned method of reading a map. In a sense, if your GPS device finds the grocery store for you, you have proven Einstein right.

Below is a YouTube video animation visualizing the GPS system.

GPS Facts

The GPS project was started by the U.S. Department of Defense in 1973. It is also owned by the U.S. Department of Defense.
The GPS satellites were sent up by the United States Air Force (and not NASA).
The first NAVSTAR satellite, later called GPS, was launched in 1978.
There are 31 GPS satellites currently in orbit.
The system requires 24 GPS satellites.
The 24-satellite system became fully operational in 1993.
The Global Positioning System cost (the US government) $1.8 billion annually to operate and maintain.
The Global Positioning System is free to use for the public worldwide.
Making GPS free to civilians worldwide was a decision by President Ronald Reagan in 1983 after a Korean airliner was shot down for straying off course.
GPS satellites carry extremely accurate atomic clocks. As explained, GPS must account for relativity, special relativity as well as General Relativity.
Other satellite systems help improve GPS, including WAAS (in the U.S.), EGNOS (in Europe), and MSAS (in Japan).
GPS is not the only satellite navigation system. Other countries have their own satellite navigation systems. GLONASS (Russia), Galileo (EU), and BeiDou (China).
Ukraine is helped by both GPS and Galileo.
Russian forces have been actively jamming GPS signals in Ukraine.

Uses of GPS

Examples of consumer electronics that use GPS are smart phones, tablets, Smartwatches, Car navigation systems, Cameras (DSLR with GPS), some models of laptops, fitness trackers (Fitbit), and drones.
Examples of vehicles using GPS are cars, delivery vans, trucks, aircraft, trains, ships and boats.
Military uses of GPS include guided missiles, guided munitions, tactical radios, communication systems, soldier-worn devices for location tracking, military vehicles and military aircraft.
Additional examples of GPS use include construction equipment for site positioning and machine guidance, tractors for precision farming and other agricultural machinery, surveying equipment, pipeline inspection drones, other inspection drones and rovers, emergency locator beacons, pet trackers, smart collars, livestock monitoring, personal trackers, and geocaching devices.

As you can see, GPS is extremely useful, and there are a lot of interesting facts about GPS.

To see the other Super Facts click here

The Surprising Monty Hall Problem

Superfact 22: Suppose you’re on a game show, and you’re given the choice between three doors: Behind one door is a car; behind the other two doors there are goats. You want to pick the car. You pick a door, and the host, who knows what’s behind the three doors, opens another door revealing a goat. Now the question is, is it to your advantage to switch door choice? The answer is yes. And that is the surprising Monty Hall Problem.

It is quite common to argue that it does not matter. You don’t know what is behind the two remaining doors so it should be 50/50 right? In a test involving 228 people only 13% chose to switch. However, you should switch.

Monty Hall, the gameshow host of the Let’s Make a Deal television game show, knows where the car is, so he never chooses the door with the car. And by curating the remaining two doors for you, he raises the odds that switching is always a good bet. By switching your choice, you have a 2/3 chance of winning the car but if you stay with your original choice, you only have a 1/3 chance of winning the car.

So why is this a super-fact? First, we know it is true. It is mathematically proven and experimentally verified that switching door is the best choice. Secondly, this was widely contested and is still surprising to people. Finally, probabilistic thinking is the key to being rational and making good decisions. This fact is true, important and disputed and thus a super fact.

One way of viewing the situation is by noting that there is a 1/3 chance that the car is behind any door that the contestant picks and a 2/3 chance that the car is behind one of the other two doors.

The picture shows three doors, one marked 1/3 and two more grouped together under 2/3 | The Surprising Monty Hall Problem — The car has a 1/3 chance of being behind the contestant’s pick and a 2/3 chance of being behind the other two doors. Picture from Wikimedia commons public domain.

If Monty opens one of the two doors that the contestant did not pick there is still a 1/3 probability that the car is behind the door the contestant picked and a 2/3 chance that the car is behind one of the other two doors. However, one of the doors that the contestant did not pick is now known to feature a goat. Therefore, the probability that the car is behind the other door is 2/3.

The picture shows three doors, one marked 1/3 and two more grouped together under 2/3. The last door has a goat, and it is marked by 0. The door in the middle is marked by 2/3. — The host opens a door. The odds for the two sets don’t change but the odds become 0 for the open door and 2/3 for the closed door. Picture from Wikimedia commons public domain.

The table below is probably (no pun intended) a better way of illustrating the situation. In the table door 1 is the door designated to be the contestant’s first choice. Monty opens one of the remaining doors that has a goat behind it.

Behind door 1	Behind door 2	Behind door 3	Result if staying at door 1	Result if switching to door offered.
Goat	Goat	Car	Wins goat	Wins Car
Goat	Car	Goat	Wins goat	Wins Car
Car	Goat	Goat	Wins Car	Wins goat

There are various other ways of explaining the situation including Steven Pinker’s approach. It is easy to test this is real life and repeated experiments and simulations shown that if you switch you have a 2/3 chance of winning.

As an example of the controversy this probability puzzle caused was Marily Savant’s column in Parade Magazine. As a side note, Marilyn Vos Savant is the person who has the highest recorded intelligence quotient (IQ) as stated in the Guinness Book of Records. In response to a question regarding the Monty Hall game show problem she wrote that you should switch. She received letters from 10,000 readers disputing this, including 1,000 with PhDs. In the long run she prevailed.

To see the other Super Facts click here

Neutering or spaying a dog at 6 months old can be dangerous to their health

Superfact 21: Neutering or spaying a dog at 6 months old can be dangerous to their health depending on breed. It is often recommended that you should neuter or spay your dog by the age of 6 months even as early as 8 weeks. This may be OK for some smaller breeds but is dangerous to the health and longevity of many larger breeds.

Many dog welfare organizations, SPCA, ASCA, etc., recommend that dogs are neutered or spayed by the age of 6 months, or even as early as 8 weeks. It is also a common advice in dog books.

In addition, some veterinarians still hold onto this belief. It is easy to understand why. Dogs running loose and causing unwanted pregnancies resulting in puppies having to be euthanized is a sad problem we don’t want.

Unfortunately, research has shown that neutering or spaying a dog at 6 months old can be dangerous to their health depending on the breed. You may need to wait 18 months or two years, and some breeds should not be neutered at all. In addition to the scientists in the relevant fields, professional and certified breeders, AKC and dog breed clubs and veterinarians who kept themselves informed on this issue are all aware of this.

In other words, we know this to be true, it is an important fact since so many of us own a dog, roughly half of all US households do, and yet this information is highly surprising to many. This is why I consider it a super fact.

Our yellow lab Baylor is on the left. Our brown-black German Shepherd Baby is on the right | Neutering or spaying a dog at 6 months old can be dangerous to their health depending on breed — This is our Labrador Baylor and German Shepherd Baby. Too early neutering and spaying can severely harm their health.

This less than a year-old article from the AKC states that “an age of six to nine months of age may be appropriate for neutering or spaying a toy breed puppy or small breed puppy but a larger or giant breed may need to wait until they are near or over 12-18 months of age.” The article also provides the following interesting information.

Research conducted by the University of California – Davis reveals that for some dog breeds, neutering and spaying may be associated with the increased risks of certain health conditions such as joint disorders including hip or elbow dysplasia, cranial cruciate rupture or tear, and some cancers, such as lymphoma, mast cell tumor, hemangiosarcoma, and osteosarcoma.

The research conclusions are not surprising. Sex hormones are important in the development of any animal. We know they affect psychological development as well as the musculoskeletal, cardiovascular, and the immune system.

I believe this is the University of California – Davis article in question. It is from 2020. Notice that the suggested guidelines for age of neutering is beyond 23 months for several of the giant breeds in the table featuring 35 breeds.

Bronco, our Leonberger puppy is looking straight into the camera. He is wearing a red bandana | Neutering or spaying a dog at 6 months old can be dangerous to their health depending on breed — Our three months old Leonberger Bronco. The Leonberger is a giant breed you can neuter when they are older than two years old.

Recommended Ages for Neutering and Spaying

Below is a list of recommended ages for neutering and spaying for selected dog breeds.

Australian Shepherd, for neutering and spaying it is your choice.
Bernese Mountain Dog, you should neuter beyond the age of 23 months, but for spaying you have a free choice.
Boxer, neuter and spay beyond the age of 23 months.
Boston Terrier, neuter beyond 11 months, but for spaying you have a free choice.
Doberman Pincher, never neuter, and you need to spay beyond the age of 23 months.
German Shepherd, neuter and spay beyond the age of 23 months.
Labrador Retriever, neuter beyond 6 months and spay beyond 11 months.
Corgi, neuter beyond 6 months, but for spaying you have a free choice.
Great Dane, despite being a very large dog you have a free choice for both neutering and spaying.
Rottweiler, neuter beyond 11 months, but for spaying beyond 6 months.

A mini-Australian Shepherd puppy is peeking out behind a sofa chair. — Our mini-Australian Shepherd puppy Rollo. You can neuter this breed at an earlier age.

We used to own a male Leonberger dog, which is a giant breed. Our breeder told us to wait beyond two years before neutering him, for health reasons. This article from Hillhaven Leonbergers states the following “We recommend not neutering until at least 2 years of age…Some Vets would recommend from 6 months but this is NOT a good idea.” To read more about the neutering and spaying of Leonberger dogs click here.

Our Leonberger dog Bronco is standing on a red leather sofa. He is stretching to give me a hug. — Our Leonberger dog Bronco is giving me a hug. He was about one year old in the picture. That is still too early to neuter him.

This article from the Saint Bernard Club of America states that “above all, no giant breed puppy should be altered before the growth plates in the bones have matured and closed, usually between 15 and 24 months of age.” This Newfoundland dog magazine states : Currently, the recommended age that a Newfoundland dog should be neutered is 18 to 24 months due to the possible health problems that can arise from altering before that age.

A Saint Bernard dog carrying the typical cognac container. There are mountains in the background | Neutering or spaying a dog at 6 months old can be dangerous to their health depending on breed — According to the article above you should wait to neuter Saint Bernard Dogs until they are close to two years old. Saint Bernard Stock Photo ID: 1713912484 by fred12.

A dark brown Newfoundland dog standing on a stump in the forest. — According to the article above you should wait to neuter Newfoundland Dogs until they are between 18 to 24 months old. Newfoundland dog Stock Photo ID: 1925281937 by Marsan.

Even though the expert advice regarding the best age for neutering and spaying varies, it is clear that doing it at six months old is too early for many breeds and can harm their health.