Another definition of irony (Page 3)

The 'very likely to intensify' is because there is very good agreement among the models that that's whats going to happen.  There's greater uncertainty about predicted changes in precip than temperature since it has much greater spatial variability and is more influenced by human actions (us putting aerosols in the atmosphere) and natural variation (eg. ENSO's), but over the last few years model's skill has been improving and even though the spatial variability of changes in precip has a higher level of uncertainty, uncertainty doesn't equal ignorance.  The takeway is that there's good agreement that in general, the wet get wetter and the dry get dryer.  And overall, there's absolutely no dispute that a warmer atmosphere can hold more water and it's only common sense that what goes up has to come back down (which is why even though water vapor is the most potent GHG there is it doesn't act as a forcing agent).

From the most recent IPCC (AR5) and Extreme Events Report:

"Regional trends in precipitation extremes since the middle of the 20th century are varied (Table 2.13). In most continents confidence in trends is not higher than medium except in North America and Central America and Europe where there have been likely increases in either the frequency or intensity of heavy precipitation. This assessment increases to very likely for central North America. For North America it is also likely that increases have occurred during the whole of the 20th century (Pryor et al., 2009; Donat et al., 2013c; Villarini et al., 2013). For South America the most recent integrative studies indicate heavy rain events are increasing in frequency and intensity over the continent as a whole (Donat et al., 2013c; Skansi et al., 2013). For Europe and the Mediterranean, the assessment masks some regional and seasonal variation. For example, much of the increase reported in Table 2.13 is found in winter although with decreasing trends in some other regions such as northern Italy, Poland and some Mediterranean coastal sites (Pavan et al., 2008; Lupikasza, 2010; Toreti et al., 2010). There are mixed regional trends across Asia and Oceania but with some indication that increases are being observed in more regions than decreases while recent studies focused on Africa, in general, have not found significant trends in extreme precipitation (see Chapter 14 for more on regional variations and trends)."

AND 

"It is likely that the frequency of heavy precipitation or the proportion of total rainfall from heavy falls will increase in the 21st century over many areas of the globe. This is particularly the case in the high latitudes and tropical regions, and in winter in the northern mid-latitudes. Heavy rainfalls associated with tropical cyclones are likely to increase with continued warming. There is medium confidence that, in some regions, increases in heavy precipitation will occur despite projected decreases in total precipitation in those regions. Based on a range of emissions scenarios (B1, A1B, A2), a 1-in-20 year annual maximum daily precipitation amount is likely to become a 1-in-5 to 1-in-15 year event by the end of the 21st century in many regions, and in most regions the higher emissions scenarios (A1B and A2) lead to a stronger projected decrease in return period."

BTW - the tropical cyclone section was just below & sounds pretty unchanged: increase in intensity but no change or decrease in frequency.

lol, I believe that could be measured and correlated but the causation may still be a challenge to prove.  

For the record, I'm not the only crazy person out there.  My MIT buddy is back in the news and he sums up my point of view pretty well.  

What Catastrophe? MIT’s Richard Lindzen, the unalarmed climate scientist

Well I mean, I'm not a climate scientist and some of that stuff goes over my head, so take this for what its worth.  That post is just ramblings on the web, it hasn't been published or peer reviewed or anything, but I think I can see a few problems with this analysis.

For one, he's using the data inappropriately.  The NASA team in charge of the NVAP mission (the data he uses to say stratospheric water vapor is decreasing) says explicity that their data shouldn't be used for trends - they say "There are several natural events and especially data and algorithmic time-dependent  biases that cause us to conclude that the extant NVAP dataset is not currently suitable for detecting trends in total precipitable water (TPW) or layered water vapor on decadal scales." To go along with that, other data sets such as the Boulder radiosonde (which he himself says is reliable and we should believe) actually show an increasing trend and the most recent IPCC report says "In summary, near-global satellite measurements of stratospheric H2O show substantial variability for 1992–2011, with a step-like decrease after 2000 and increases since 2005. Because of this large variability and relatively short time series, confidence in long-term stratospheric H2O trends is low." So from the get-go, his assertion that SWV is decreasing is pretty suspect.

Another problem is that he makes the assumption that attribution of warming to CO2 hinges on "tropical hot spots", and that's not true.  Not only are these hot spots predicted no matter what the mechanism of warming (not just for GHGs, but alsoif the warming was caused by increase in solar radiation for example).  The signature of warming due to GHGs (CO2) is a cooling of the stratosphere which has unequivocably been documented.  But he's cherry picking data sets (there are 4 other radiosonde data sets he chose not to use).  According to the most recent IPCC "Globally the radiosonde records all imply the troposphere has warmed and the stratosphere cooled since 1958 but with uncertainty that grows with height and is much greater outside the better-sampled NH extra-tropics (Thorne et al., 2011; Haimberger et al., 2012), where it is of the order 0.1°C per decade".  The radiosonde data is known to be suspect but other indirect studies looking at wind shear and precip to determine stability and then temp in the upper atmosphere) have found it's basically behaving as the models expect, but without better data it's hard to say for sure.

As best I can tell he's inappropriately using data and then cherry picking data sets and then making a straw man argument about tropical hot spots (and again misusing data there too).  There are definitely uncertainties, especially surrounding the warming of the upper troposphere.  It's very hard to measure and even though much of the evidence is pointing towards the models being right, it isn't a done deal.  And the same with stratospheric water vapor.  Better measurements are definitely needed and more research needs to be done.  Especially since if the Boulder data are correct (it's only one data set and needs to be corraborated with others) recent research points to it being a bad thing.