HIstory of Global dimming
From a simple finding to one of the biggest climate changing factors
of the 21st century - Global Dimming. How did it all start?
Global dimming was first discovered 40 years ago by a British Scientist named Gerry Stanhill who at that time was developing an irrigation system in Israel. One of the things that he had to do was to measure the solar radiation of the sun of that time. In his documentary that followed, he explained how amazed he was that the solar radiation of this time was much less than 20 years ago. When he then gathered data from other European countries, he also saw this trend of decreasing sunlight.
"Well I was amazed to find that there was a very serious reduction in sunlight, the amount of sunlight in Israel. In fact, if we compare those very early measurements in the 1950s with the current measurements, there was a staggering 22% drop in the sunlight, and that really amazed me." - Gerry Stanhill
He then published his findings in a science journal in 2001, explaining his findings and also his theory, but to his dismay, scientist did not take his findings. A bit later in the future, another young climatologist in Germany named Beate Liepart found that the same thing seem to be happening over the Bavarian Alps.
"I was the same, I was as skeptical as any other climatologist. But then, um, I, I saw the same results er in Germany, so um I believed him." - Dr Beate Liepert
Individually, they collected data from all over the world from meteorologist, publications and journals. And both found a surprising common factor. There was a decrease in solar radiation level all over the world. Between the 1950's and the 1990's, the levels of solar radiation have dropped by 9% in Antartica, 10% in USA, by almost 30% in Russia and also 16% in parts of the British Isles. From these statistics, it could be clearly seen that this was a global phenomenon, Gerry then gave it a suitable name - Global Dimming. Since this climate changing factor did not seem to fit in with Global warming, people simply dismissed the idea.
Elsewhere in the world, Australia to be precise, two biologist were intrigued by another paradoxical result - A decline in something called the pan evaporation rate.
of the 21st century - Global Dimming. How did it all start?
Global dimming was first discovered 40 years ago by a British Scientist named Gerry Stanhill who at that time was developing an irrigation system in Israel. One of the things that he had to do was to measure the solar radiation of the sun of that time. In his documentary that followed, he explained how amazed he was that the solar radiation of this time was much less than 20 years ago. When he then gathered data from other European countries, he also saw this trend of decreasing sunlight.
"Well I was amazed to find that there was a very serious reduction in sunlight, the amount of sunlight in Israel. In fact, if we compare those very early measurements in the 1950s with the current measurements, there was a staggering 22% drop in the sunlight, and that really amazed me." - Gerry Stanhill
He then published his findings in a science journal in 2001, explaining his findings and also his theory, but to his dismay, scientist did not take his findings. A bit later in the future, another young climatologist in Germany named Beate Liepart found that the same thing seem to be happening over the Bavarian Alps.
"I was the same, I was as skeptical as any other climatologist. But then, um, I, I saw the same results er in Germany, so um I believed him." - Dr Beate Liepert
Individually, they collected data from all over the world from meteorologist, publications and journals. And both found a surprising common factor. There was a decrease in solar radiation level all over the world. Between the 1950's and the 1990's, the levels of solar radiation have dropped by 9% in Antartica, 10% in USA, by almost 30% in Russia and also 16% in parts of the British Isles. From these statistics, it could be clearly seen that this was a global phenomenon, Gerry then gave it a suitable name - Global Dimming. Since this climate changing factor did not seem to fit in with Global warming, people simply dismissed the idea.
Elsewhere in the world, Australia to be precise, two biologist were intrigued by another paradoxical result - A decline in something called the pan evaporation rate.
Pan EVAPORATION rate
Basically pan evaporation rate is when you measure evaporation from a pan. In the morning, you fill up a pan full of water and in the evening you measure the amount that has been evaporated by seeing how much water you need to fill it up back to the original water level.
Professor Graham Farquhar and Michael Roderick were curious of how in the 1990's, the pan evaporation rate was going down. The general response was that with Global warming heating up the earth, shouldn't the evaporation rate go up? They investigated and found out that the key requirement needed more evaporation was not hot temperatures but sunlight, humidity and the wind.
The photons of the light is needed to kick the water particles off the surface of the water. Then, they reached a conclusion. If the pan evaporation rate was falling, then that also meant that sunlight could also be decreasing. They then found the statistics that Gerry and Beate published, and concluded that Global dimming was real.
Professor Graham Farquhar and Michael Roderick were curious of how in the 1990's, the pan evaporation rate was going down. The general response was that with Global warming heating up the earth, shouldn't the evaporation rate go up? They investigated and found out that the key requirement needed more evaporation was not hot temperatures but sunlight, humidity and the wind.
The photons of the light is needed to kick the water particles off the surface of the water. Then, they reached a conclusion. If the pan evaporation rate was falling, then that also meant that sunlight could also be decreasing. They then found the statistics that Gerry and Beate published, and concluded that Global dimming was real.
"and concluded that Global dimming was real."