Science is our current understanding of things. Our current understanding of things changes over time. Many things that used to be known as scientific fact in the past were wrong. In the future, we will probably discover that some things that are known as scientific fact today are wrong too. It is important to keep this in mind as scientists make more discoveries because not everything they discover is true.
Scientists discover things through observation and experimentation. They analyze the data. They make theories. They draw conclusions. Some of them do a good job, but others, not so much.
Here are some examples of things that some people used to believe that were later proven wrong. People used to believe that the sun, stars, and planets orbited the earth. Now we know that the earth and the other planets orbit the sun. People used to believe that the earth is flat. Now we know that the earth is round. People used to believe that when materials burn, they release an element called phlogiston. Now we know that there is no such thing as phlogiston. Burning materials don't release phlogiston. They consume oxygon.
In the 1970s, some people believed in global cooling. There was fear of a future ice age. Now we know that we don't have to worry about global cooling, but why were people worried about it in the 1970s? It's because the media talked about it a lot. We can't always trust the media.
Theories often get misstated as facts. Scientists don't always do a good job researching things. Some of them jump to unjustified conclusions and analyze the data in unreliable ways because they're way too determined to prove their theories. There were theories misstated as facts in the past. There are theories misstated as facts today too. Bad science gets promoted by business men and politicians who have financial self interests and political agendas.
Here is one example of a theory that has been misstated as fact today. Global warming. A lot of people are worried about the earth heating up. Let's take a careful look at the changes in the average global temperature over time.
The graph above is from NASA's GISS(Goddard Institute for Space Studies). The graph shows global temperature anomalies. A temperature anomaly of zero degrees is considered normal. For GISS, normal is the average temperature from 1951 to 1980, which is about 14.0 degrees Celsius(57.2 degrees Fahrenheit). A temperature anomaly that is more than zero degrees is considered warmer than normal. A temperature anomaly that is less than zero degrees is considered colder than normal. It is important to understand the data shown by the graph. Here is another way to look at the data.
The data in the second graph is exactly the same data as the data in the first graph. The difference between the two graphs is the y-axis. In the first graph, the y-axis has -0.6 degrees at the bottom and 0.6 degrees at the top. Each number on the y-axis is 0.2 degrees apart. In the second graph, the y-axis has -6 degrees at the bottom and 6 degrees at the top. Each number on the y-axis is 2 degrees apart. The first graph shows the data in a very tiny temperature range. The average global temperature hasn't really changed much. The data only shows that there has been slight increases and slight decreases in temperature over time. To understand the data that is shown in graphs, it is important to look at both the x-axis and the y-axis.
So the average global temperature is about a degree warmer than it was a century ago. Does this mean the earth is in danger of being destroyed by global warming? No. Believers in global warming claim that even small changes in temperature cause dangerous changes in the weather, but that is a flawed assumption. There is no way to be sure that the weather is that sensitive to temperature changes. Another flawed assumption made by global warming believers is that the temperature changes are being caused by people. Most carbon dioxide is caused by natural processes such as oceans and volcanic eruptions. Only about 3% of carbon dioxide is man made.
Global warming believers claim that the man made carbon dioxide distrupts the balance in the carbon cycle. When disasters such as storms, floods, and droughts happen, they blame those disasters on man made global warming, but there is really no way to know that the disasters were caused by people. The disasters were really caused by natural processes. The weather has always been changing. Disasters such as storms, floods, and droughts have happened all throughout the history of the earth, even before humans started burning fossil fuels. Humans can not control the weather. Changes in the weather are natural, not man made.
The way in which the data is measured makes a difference. While NASA's data shows a slight increase in temperature, RSS(remote sensing systems) satellite data shows that there was no global warming for over 18 years. The RSS satellite data is shown below.
The most logical conclusion to make is that there is no global warming, at least no significant global warming, and even if there is global warming, humans do not have any impact on it, at least not any significant impact.
Here is another example of a theory that has been misstated as fact today. The theory that saturated fats cause heart disease. That theory is false. Saturated fats do not cause heart disease. The scientist who made that theory is Ancel Benjamin Keys. He published the seven countries study. The study shows seven countries. For each country, the study shows how much saturated fat was eaten by the people in that country and how many of the people died from heart disease.
Ancel Keys had information from 22 countries but he only picked 7 of those countries. He picked the countries that supported his theory and ignored the countries that didn't support his theory. Here is the study that shows all 22 countries.
This study shows a number for each country. Here is a list of the countries that are represented by the numbers.
There are many things that can cause heart disease such as smoking, air pollution, lack of excercise, and many other causes of heart disease. So when people have heart disease, there is really no proof that it was caused by eating too much saturated fat. The study does not show much evidence for Ancel Keys's theory. Ancel Keys cherry-picked the data to support his theory. He ignored other things that can cause heart disease and he ignored most of the countries. Cherry-picking data and ignoring other factors is not good science. It's bad science.
Unfortunately, that's how a lot of bias scientists do their research. There are a lot of bias scientists, but there are also a lot good scientists. Bad science does get challenged, but many business men and politicians try to promote the bad science for their financial and political reasons. The media likes to use scare stories to get people's attention such as global cooling, global warming, and saturated fats causing heart disease. They care more about making money then they do about being accurate. So don't believe everything you hear or read.