His task was to measure how strongly the sun shone over Israel. -Because there was a staggering 22% drop in the sunlight, and that really amazed him. A 22% drop in solar energy was simply massive. If it was true surely Israelis should be freezing. There had to be something wrong. -In Israel -He found that there was a very serious reduction in sunlight, the amount of sunlight in Israel. -No. • Who was the German scientist who collaborated with Stanhill? Beate Liepert – What did she find in the Bavarian Alps?
She found that there was reduction in sunlight. – What did she and Stanhill find when they checked records from 1950 to 1990? Between the 1950s and the early 1990s the level of solar energy reaching the earth’s surface had dropped 9% in Antarctica, 10% in the USA, by almost 30% in Russia. And by 16% in parts of the British Isles. – What sort of records did they check? They have checked the publication, journal and meteorological records all around the world. – Why was their work again dismissed?
The scientific community was obviously not ready to deal with the fact that there was a Global Dimming phenomena the response from other scientists was one of sheer disbelief. and the research was extreme and billions of dollors was spent on global warming research and they are contradicting to other scientists . • What sort of data did the Australian researchers find? There is a paradox here about the fact that the pan evaporation rate’s going down, an apparent paradox, but the global temperature’s going up. – Who were they?
Michael Roderick and Graham Farquhar – What did they find? They were intrigued by another paradoxical result – the world-wide decline in something called the pan evaporation rate. – Was there published data supporting their findings? For decades, nobody took much notice of the pan evaporation measurements. But in the 1990s scientists spotted something very strange, the rate of evaporation was falling. • What is the pan evaporation measurement? It’s called pan evaporation rate because it’s evaporation rate from a pan. • What factors affect pan evaporation? he key things for pan evaporation are the sunlight, the humidity and the wind. The sunlight is a really dominant term there. • Which is dominant? The sunlight. • Is there a correlation between drop in evaporation and sunlight? The drop in evaporation with the drop in sunlight. The drop in evaporation rate matched exactly the drop in sunlight. • What is considered responsible for global dimming? particle pollution, which forms the airborne particles are responsible for global dimming. • Who was responsible for proving it? PROF VEERABHADRAN RAMANATHAN Where was the experiment conducted? The Maldives. • What was the evidence? Almost everything we do to create energy causes pollution. The stunning part of the experiment was this pollutant layer which was three kilometre thick, cut down the sunlight reaching the ocean by more than 10%. • Why do particles reduce sunlight? In the polluted air billions of man-made particles provided ten times as many sites around which water droplets could form. So polluted clouds contained many more water droplets, each one far smaller than it would be naturally.
Many small droplets reflect more light than fewer big ones. So the polluted clouds were reflecting more light back into space, preventing the heat of the sun getting through. This was the cause of Global Dimming. • Why is global dimming thought to be linked to drought in the Sahel? The Sahel’s lifeblood has always been a seasonal monsoon. For most of the year it is completely dry. But every summer, the heat of the sun warms the oceans north of the equator. This draws the rain belt that forms over the equator northwards, bringing rain to the Sahel.
Polluted clouds stopped the heat of the sun getting through. That heat was needed to draw the tropical rains northwards. So the life giving rain belt never made it to the Sahel. Global dimming could have been behind this drought. • What is the most convincing evidence of the effect of particles on reducing temperature? If we carried on pumping out the particles it would have terrible impact on human health,this means particles are involved in all sorts of respiratory diseases, that’s why they’re being brought under control, and of course they effect climate anyway.
If fiddle with the balance of the planet, the radiative balance of the planet, you affect all sorts of circulation patterns like monsoons, which would have horrible effects on people. So it would be extremely difficult, in fact impossible, to cancel out the greenhouse effect just by carrying on pumping out particles, even if it wasn’t for the fact that particles are damaging for human health. • What are the likely consequences of reducing pollution from particulates?
If we carried on pumping out the particles it would have terrible impact on human health,this means particles are involved in all sorts of respiratory diseases, that’s why they’re being brought under control, and of course they effect climate anyway. If fiddle with the balance of the planet, the radiative balance of the planet, you affect all sorts of circulation patterns like monsoons, which would have horrible effects on people. So it would be extremely difficult, in fact impossible, to cancel out the greenhouse effect just by carrying on pumping out particles, even if it wasn’t for the fact that particles are damaging for human health.