number of particles not their mass. The number of liquid drops is many orders of magnitude smaller than the number of gas molecules that have condensed into those drops. Therefore, condensation immediately lowers air pressure and disturbs the hydrostatic equilibrium. Recently a paper devoted to this question was published in a leading meteorological journal where, with use of numerical modeling, this conclusion was articulated. That a paper with such a basic conclusion has appeared only nowin the second decade of the Twenty First Centurydemonstrates that the efforts to study the dynamic effects of condensation by the meteorological community are in their incipient stage. In the meantime, practically all climate and weather phenomena where condensation and precipitation are involved are challenging modern meteorology. For example, the existing global circulation models do not adequately describe the water cycle in the Amazon, with the modeled moisture convergence being half the actual amounts estimated from the observed runoff values. It is widely recognized that despite the ever-improving observation facilities and the available computer power, there is no progress in predicting the intensity of tropical cyclones. When analyzing how precipitation changes with time (e.g., in the Amazon or Congo regions) it is common to explore correlations with oceanic temperature anomalies. The conventional logic is that as the ocean becomes warmer, the warm air rises over the ocean and moisture precipitates there rather than over land, hence a drought occurs. However, such logic does not take into account that as the land becomes drier, it also warms significantly. It is unexplainable within the conventional paradigm why the warm air does not rise over the hot and dry land. All heat waves and droughts, like the one in European Russia in 2010 or the one in Texas in 2011, are associated with persistent descending air motion. Neither are flooding events explained by the conventional paradigm. For example, of the two extreme floods that hit Thailand in 2011, the first one occurred early in the year during the dry season. Then the land is cooler, the ocean is warmer and winds blow from land to the ocean, so that the continent remains dry. In early 2011 the region was struck by an unusual cold wave, which caused this temperature gradient to become even more pronounced. According to the conventional paradigm, this should only strengthen dry conditions. In reality, however, a major flooding happened. Evidence of this type, which is controversial with respect to the conventional paradigm, is mounting and the biotic pump concept gives a consistent physical explanation of how this should be interpreted. Rather than focusing on temperature gradients, which are often a consequence rather than cause of the circulation, one should investigate the conditions when condensation is likely to occur to predict changes in atmospheric circulation. REGIONAL EXAMPLES OF THE BIOTIC PUMP The Maya city of Tulum. Research is adding up that deforestation may have been a large factor in the decline of the Mayan civilization. Photo by: Rhett A. Butler.Mongabay: Recent evidence has linked the decline and fall of the Maya civilization to deforestation leading to less