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Prediction:I predict that raising the light intensity will increase the rate of photosynthesis.

BBC - GCSE Bitesize: Photosynthesis summary

Professor Roger Pielke Jr. of the University of Colorado Boulder: “The world is presently in an era of unusually low weather disasters. This holds for the weather phenomena that have historically caused the most damage: tropical cyclones, floods, tornadoes and drought. Given how weather events have become politicized in debates over climate change, some find this hard to believe...The US has seen a decrease of about 20% in both hurricane frequency and intensity at landfall since 1900...Data on floods, drought and tornadoes are similar in that they show little to no indication of becoming more severe or frequent...Thus, it is fair to conclude that the costs of disasters worldwide is depressed because, as the global economy has grown, disaster costs have not grown at the same rate. Thus, disaster costs as a proportion of GDP have decreased. One important reason for this is a lack of increase in the weather events that cause disasters, most notably, tropical cyclones worldwide and especially hurricanes in the United States.”

I then think that the rate of photosynthesis will stay the same when it reaches a certain point.

IB Biology Notes - 8.2 Photosynthesis

When Wangsness says that “not one of them has broken ranks and busted the hoax,” he is wrong. There are scores of top scientists in relevant fields like atmospheric physics and meteorology who have broken ranks and scream as loudly as they can on a daily basis that there is nothing behind this alarm. Just last October I was involved in submitting a letter to EPA from 65 top scientists demanding a reconsideration of EPA’s “Endangerment Finding” because of lack of scientific basis for climate alarm. The list of skeptics among the very top people in physics includes the likes of Freeman Dyson ("My first heresy says that all the fuss about global warming is grossly exaggerated. Here I am opposing the holy brotherhood of climate model experts and the crowd of deluded citizens who believe the numbers predicted by the computer models.") and Will Happer of Princeton, Richard Lindzen of MIT, and Ivar Giaever of RPI. It is truly an embarrassment to the profession of journalism that a relatively well-informed citizen like Mr. Wangsness can be unaware of this.

This process is called photosynthesis. Temperature, carbon dioxide concentration and light intensity are factors that can limit the rate of photosynthesis.


Earth's climate is a complex system controlled by many factors

Prediction: I predict that as the light source (desk lamp) is moved closer to the pondweed (Elodea), the rate of photosynthesis will increase therefore more oxygen will be produced creating more bubbles.

photosynthesis notes - Biology Junction

Prediction: I predict that the oxygen bubbles will decrease when the lamp is further away from the measuring cylinder, because light intensity is a factor of photosynthesis.

BBC - GCSE Bitesize: Photosynthesis

So how can these factors have an effect on the rate of photosynthesis? Lets start off with the light intensity. When the light intensity is poor, there is a shortage of ATP and NADPH, as these are products from the light dependent reactions. Without these products the light independent reactions can't occur as glycerate 3-phosphate cannot be reduced. Therefore a shortage of these products will limit the rate of photosynthesis. When the carbon dioxide concentration is low, the amount of glycerate 3-phosphate produced is limited as carbon dioxide is needed for its production and therefore the rate of photosynthesis is affected. Finally, many enzymes are involved during the process of photosynthesis. At low temperatures these enzymes work slower. At high temperatures the enzymes no longer work effectively. This affects the rate of the reactions in the Calvin cycle and therefore the rate of photosynthesis will be affected.

Climate Change: Vital Signs of the Planet: Evidence

A limiting factor is a factor that controls a process. Light intensity, temperature and carbon dioxide concentration are all factors which can control the rate of photosynthesis. Usually, only one of these factors will be the limiting factor in a plant at a certain time. This is the factor which is the furthest from its optimum level at a particular point in time. If we change the limiting factor the rate of photosynthesis will change but changes to the other factors will have no effect on the rate. If the levels of the limiting factor increase so that this factor is no longer the furthest from its optimum level, the limiting factor will change to the factor which is at that point in time, the furthest from its optimum level. For example, at night the limiting factor is likely to be the light intensity as this will be the furthest from its optimum level. During the day, the limiting factor is likely to switch to the temperature or the carbon dioxide concentration as the light intensity increases.

Student Sheet 3 - Investigating Photosynthesis with …

That is only the beginning of the problematic factual assertions and assumptions underlying the children’s lawsuit. The measurable effects of increasing GHG concentrations are far smaller than the climate models would lead one to believe. The degree to which recent warming has been anthropogenic is unsettled in the scientific literature; and the Intergovernmental Panel on Climate Change (IPCC) in its fifth assessment report (AR5) has reduced its estimated range of the effect in 2100 of a doubling of GHG concentrations from 2.0-4.5 to 1.5-4.5 degrees C.