Global Warming has not accelerated the Water Cycle in the last 115 years

The Water CycleI want to start by providing a brief description of the water cycle, and what it means to accelerate the water cycle. At the most basic level, the water cycle is the explanation of why precipitation occurs. Water evaporates from the oceans as a result of solar heat input, rises into the atmosphere, condenses as the air gets cooler (forming clouds), moves on land, releases its water, which heads back circuitously into the ocean. Here is a picture showing the many intricacies of the water cycle: [1]The acceleration of the water cycle would mean that the cycle is becoming stronger - more water evaporates, implying that more precipitation occurs. It is my burden, then, to show that more precipitation is occurring now compared to 115 years ago. Global Warming and the Water CycleAt the most basic level, a warmer climate would mean that there would be more precipitation, because more water would evaporate from the oceans, due to the fact that the chance of a water molecule in the oceans breaking free of its bonds with other water molecules would be more likely to escape, and given enougn kinetic energy (and it's moving in the right direction), the water would do so. While the climate does work like this, the climate is a bit more complicated than that. Some places will get dryer because warmer climates dry the soil out faster, and regions that don't typically get a lot of rain can suffer as a result. There are many ways one can observe an acceleration of the climate cycle. One obvious way would be to find that the amount of precipitation falling around the Earth is increasing. This is indeed the case. "An advanced statistical analysis of rainfall data from the years 1901 to 2010 derived from thousands of weather stations around the globe shows that over 1980-2010 there were 12 percent more of these events than expected in a stationary climate, a scenario without global warming. " This seems to show that global warming is accelerating the water cycle. However, there are many other indicators that this is so. [2]One could look at how much water is being evaporated from the oceans and how much water is running off in rivers, for example (we'd expect an increase in both of these indicators). A measure of how much water is being evaporated is humidity - a measure of the "saturation" of the atmosphere (the atmosphere can only hold so much water vapor; humidity measures the percentage of this amount). The greater the evaporation, the greater the global humidity, because there's more water vapor in the atmosphere. "All five reanalyses produce similar relations, with increasing surface temperature being associated with increasing atmospheric specific humidity. These results agree with previous analyses that the water vapor feedback in response to shortR08; term variations is strongly positive. This is also consistent with P09, who looked at the seasonal cycle in the extratropics in the NCEP/NCAR reanalysis and found that it showed a positive correlation between surface temperature and 500 hPa specific humidity. "[3]How much water is being run off in rivers? "For the relatively short 13-year period studied here, global discharge increased by 540 km^3W25;y^2 [this is a rate of approximately 1.5 percent a year], which was largely attributed to an increase of globalocean evaporation (768 km^3W25;y^2). Sustained growth of these flux rates into long-term trends would provide evidence for increasing intensity of the hydrologic cycle. " A graph of this increase can be seen below[4][5]: The data that clouds give us is more difficult to understand. You'd think that more evaporation would entail there being more clouds, but this isn't necessarily true. The way clouds work is much more complicated than that. In addition, you have to contend with the feedbacks that clouds cause. What is the evidence that the acceleration of the water cycle is due to global warming? Well, warmer air holds more moisture. We'd expect precipitation increases to follow the change in the temperature of the atmosphere. "While a statistical analysis of course cannot provide direct physical cause-effect relations, the scientists compared their findings to existing knowledge about how much more water can be stored in the atmosphere when temperatures rise, as given by the well-known Clausius-Clapeyron equation. This additional moisture can be released during short-term heavy rainfall events. The scientists show that the observed increase in unprecedented heavy rainfall events generally fits with this thermodynamically expected increase under global warming. "[2]Overall, the significant acceleration of the water cycle is unlikely to be due to any natural variation of the climate, nor is it likely to just be a statistical anomoly. The theory behind anthropogenic global warming clearly explains why the water cycle is accelerating, as a warmer atmosphere would evaporate water faster and would be able to hold more of that water vapor. ConclusionOverall, the water cycle involves evaporation, condensation, precipitation, and runoff. I've shown that evaporation (in the form of humidity), precipitation, and runoff have all increased, and this is most likely due to global warming, due to the connection between warming and the acceleration of the water cycle. Sources[1]: . https://en.wikipedia.org...[2]: . https://www.pik-potsdam.de...[3]: . http://geotest.tamu.edu...[4]: . http://www.pnas.org...[5]: . http://www.skepticalscience.com...