Showing posts sorted by relevance for query water vapor. Sort by date Show all posts
Showing posts sorted by relevance for query water vapor. Sort by date Show all posts

Wednesday, March 6, 2013

Man-made global warming theory is falsified by satellite water vapor observations

Reblogged from Clive Best and Ken Gregory at Friends of Science.org:


Water Vapor Decline Cools the Earth: NASA Satellite Data

by Ken Gregory P.Eng., Friends of Science.org

An analysis of NASA satellite data shows that water vapor, the most important greenhouse gas, has declined in the upper atmosphere causing a cooling effect that is 16 times greater than the warming effect from man-made greenhouse gas emissions during the period 1990 to 2001.
The world has spent over $ 1 trillion on climate change mitigation based on climate models that don’t work. They are notoriously poor at simulating the 20th century warming because they do not include natural causes of climate change – mainly due to the changing sun -  and they grossly exaggerate the feedback effects of greenhouse gas emissions.
Most scientists agree that doubling the amount of carbon dioxide (CO2) in the atmosphere, which takes about 150 years, would theoretical warm the earth by one degree Celsius if there were no change in evaporation, the amount or distribution of water vapor and clouds. Climate models amplify the initial CO2 effect by a factor of three by assuming positive feedbacks from water vapor and clouds, for which there is little direct evidence. Most of the amplification by the climate models is due to an increase in upper atmosphere water vapor.
The Satellite Data
The NASA water vapor project (NVAP) uses multiple satellite sensors to create a standard climate dataset to measure long-term variability of global water vapor. NASA recently released the Heritage NVAP data which gives water vapor measurement from 1988 to 2001 on a 1 degree by 1 degree grid, in three vertical layers.1 The NVAP-M project, which is not yet available, extends the analysis to 2009 and gives five vertical layers. Water vapor content of an atmospheric layer is represented by the height in millimeters (mm) that would result from precipitating all the water vapor in a vertical column to liquid water. The near-surface layer is from the surface to where the atmospheric pressure is 700 millibar (mb), or about 3 km altitude. The middle layer is from 700 mb to 500 mb air pressure, or from 3 km to 6 km attitude. The upper layer is from 500 mb to 300 mb air pressure, or from 6 km to 10 km altitude.
The global annual average precipitable water vapor by atmospheric layer and by hemisphere from 1988 to 2001 is shown in Figure 1.
The graph is presented on a logarithmic scale so the vertical change of the curves approximately represents the forcing effect of the change. For a steady earth temperature, the amount of incoming solar energy absorbed by the climate system must be balanced by an equal amount of outgoing longwave radiation (OLR) at the top of the atmosphere. An increase of water vapor in the upper atmosphere would temporarily reduce the OLR, creating a forcing of more incoming than outgoing energy, which raises the temperature of the atmosphere until the balance is restored.
NVAP_pwv
Figure 1.  Precipitable water vapor by layer, global and by hemisphere.
The graph shows a significant percentage decline in upper and middle layer water vapor from 1995 to 2001. The near-surface layer shows a smaller percentage increase, but a larger absolute increase in water vapor than the other layers. The upper and middle layer water vapor decreases are greater in the Southern Hemisphere than in the Northern Hemisphere.
Table 1 below shows the precipitable water vapor for the three layers of the Heritage NVAP and the CO2 content for the years 1990 and 2001, and the change.
LayerL1 near-surfaceL2 middleL3 upperSumCO2
1013-700700-500500-300
mmmmmmmmppmv
199018.994.61.4925.08354.16
200120.724.030.9425.69371.07
change1.73-0.57-0.550.6116.91
Table 1.  Heritage NVAP 1990 and 2001 water vapour and CO2.
Dr. Ferenc Miskolczi performed computations using the HARTCODE line-by-line radiative code to determine the sensitivity of OLR to a 0.3 mm change in precipitable water vapor in each of 5 layers of the NVAP-M project. The program uses thousands of measured absorption lines and is capable of doing accurate radiative flux calculations.  Figure 2 shows the effect on OLR of a change of 0.3 mm in each layer.
The results show that a water vapor change in the 500-300 mb layer has 29 times the effect on OLR than the same change in the 1013-850 mb near-surface layer. A water vapor change in the 300-200 mb layer has 81 times the effect on OLR than the same change in the 1013-850 mb near-surface layer.
OLR_PWV_bar
Figure 2. Sensitivity of 0.3 mm precipitable water vapor change on outgoing longwave radiation by atmospheric layer.
Table 2 below shows the change in OLR per change in water vapor in each layer, and the change in OLR from 1990 to 2001 due to the change in precipitable water vapor (PWV).
L1L2L3SumCO2
OLR/PWVW/m2/mm-0.329-1.192-4.75
OLR/CO2W/m2/ppmv-0.0101
OLR changeW/m2-0.5690.6792.6132.723-0.171
Table 2.  Change of OLR by layer from water vapor and from CO2 from 1990 to 2001.
The calculations show that the cooling effect of the water vapor changes on OLR is 16 times greater than the warming effect of CO2 during this 11-year period. The cooling effect of the two upper layers is 5.8 times greater than the warming effect of the lowest layer.
These results highlight the fact that changes in the total water vapor column, from surface to the top of the atmosphere, is of little relevance to climate change because the sensitivity of OLR to water vapor changes in the upper atmosphere overwhelms changes in the lower atmosphere.
The precipitable water vapour by layer versus latitude by one degree bands for the year 1991 is shown in Figure 3. The North Pole is at the right side of the figure. The water vapor amount in the Arctic in the 500 to 300 mb layer goes to a minimum of 0.53 mm at 58.5 degrees North, then increases to 0.94 mm near the North Pole.
Nvap_lpw_1991
Figure 3. Precipitable water vapor by layer in 1991.
The NVAP-M project extends the analysis to 2009 and reprocesses the Heritage NVAP data. This layered data is not publicly available. The total precipitable water (TPW) data is shown in Figure 4, reproduced from the paper Vonder Haar et al (2012) here. There is no evidence of increasing water vapor to enhance the small warming effect from CO2.
fig4c_tpw
Figure 4. Global month total precipitable water vapor NVAP-M.
The Radiosonde Data
Water vapor humidity data is measured by radiosonde (on weather balloons) and by satellites.  The radiosonde humidity data is from the NOAA Earth System Research Laboratory here.
GlobalRelativeHumidity300_700mb
Figure 5. Global relative humidity, middle and upper atmosphere, from radiosonde data, NOAA Earth System Research Laboratory.
A graph of the global average annual relative humidity (RH) from 300 mb to 700 mb is shown in Figure 5. The specific humidity in g/kg of moist air at 400 mb (8 km) is shown in Figure 6. It shows that specific humidity has declined by 14% since 1948 using the best fit line.
SH400mb
Figure 6.  Specific humidity at 400 mb pressure level
In contrast, climate models all show RH staying constant, implying that specific humidity is forecast to increase with warming. So climate models show positive feedback and rising specific humidity with warming in the upper troposphere, but the data shows falling specific humidity and negative feedback.
Many climate scientists dismiss the radiosonde data because of changing instrumentation and the declining humidity conflicts with the climate model simulations. However, the radiosonde instruments were calibrated and the data corrected for changes in response times. The data before 1960 should be regarded as unreliable due to poor global coverage and inferior instruments. The near surface radiosonde measurements from 1960 to date show no change in relative humidity which is consistent with theory. Both the satellite and radiosonde data shows declining upper atmosphere humidity, so there is no reason to dismiss the radiosonde data. The radiosonde data only measures humidity over land stations, so it is interesting to compare to the satellite measurements which have global coverage.
Comparison Between Radiosonde and Satellite Data
The specific humidity radiosonde data was converted to precipitable water vapor for comparison with the satellite data. Figure 7 compares the satellite data to the radiosonde data for the years 1988 to 2001.
PW_NOAA&NVAP
Figure 7. Comparison between NOAA radiosonde and NVAP satellite derived precipitable water vapor.
The NOAA and NVAP data compares very well for the period 1988 to 1995. The NVAP satellite data shows less water vapor in the upper and middle layers than the NOAA data. In 2000 and 2001 the NVAP data shows more water vapor in the near-surface layer than the NOAA data. The vertical change on the logarithmic graph is roughly equal to the forcing effect of each layer, so the NVAP data shows water vapor has a greater cooling effect than the radiosonde data.
The Tropical Hot Spot
The models predict a distinctive pattern of warming – a “hot-spot” of enhanced warming in the upper atmosphere at 8 km to 13 km over the tropics, shown as the large red spot in Figure 8. The temperature at this “hot-spot” is projected to increase at a rate of two to three times faster than at the surface. However, the Hadley Centre’s real-world plot of radiosonde temperature observations from weather balloons shown below does not show the projected hot-spot at all. The predicted hot-spot is entirely absent from the observational record. If it was there it would have been easily detected.
The hot-spot is forecast in climate models due to the theory that the water vapor profile in the tropics is dominated by the moist adiabatic lapse rate, which requires that water vapor increases in the upper atmosphere with warming. The moist adiabatic lapse rate describes how the temperature of a parcel of water-saturated air changes as it move up in the atmosphere by convection such as within a thunder cloud. A graph here shows two lapse rate profiles with a larger temperature difference in the upper atmosphere than at the surface. The projected water vapor increase creates the hot-spot and is responsible for half to two-thirds of the surface warming in the IPCC climate models.
Hot_spot
Figure 8. Climate models predict a hot spot of enhanced warming rate in the tropics, 8 km to 13 km altitude. Radiosonde data shows the hot spot does not exist. Red indicates the fastest warming rate. Source: http://joannenova.com.au
The projected upper atmosphere water vapor trends and temperature amplification at the hot-spot are intricately linked in the IPCC climate theory. The declining upper atmosphere humidity is consistent with the lack of a tropical hot spot, and both observations prove that the IPCC climate theory is wrong.
A recent technical paper Po-Chedley and Fu (2012) here compares the temperature trends of the lower and upper troposphere in the tropics from satellite data to the climate model projections from the period 1981 to 2008.2 The upper troposphere is the part of the atmosphere where the pressure ranges from 500 mb to 100 mb, or from about 6 km to 15 km. The paper reports that the warming trend during 1981 to 2008 in the upper troposphere simulated by climate models is 1.19 times the simulated warming trend of the lower atmosphere in the tropics.  (Note this comparison is to the lower atmosphere, not the surface, and includes 10 years of no warming to 2008.) Using the most current version (5.5) of the satellite temperature data from the University of Alabama in Huntsville (UAH), the warming trend of the upper troposphere is only 0.973 of the lower troposphere in the tropics for the same period. This is different from that reported in the paper because the authors used an obsolete version (5.4) of the data. The satellite data shows not only a lack of a hot-spot, it shows a cold-spot just where a hot-spot was predicted.
Conclusion
Climate models predict upper atmosphere moistening which triples the greenhouse effect from man-made carbon dioxide emissions. The new satellite data from the NASA water vapor project shows declining upper atmosphere water vapor during the period 1998 to 2001. It is the best available data for water vapor because it has global coverage. Calculations by a line-by-line radiative code show that upper atmosphere water vapor changes at 500 mb to 300 mb have 29 times greater effect on OLR and temperatures than the same change near the surface. The cooling effect of the water vapor changes on OLR is 16 times greater than the warming effect of CO2 during the 1990 to 2001 period. Radiosonde data shows that upper atmosphere water vapor declines with warming. The IPCC dismisses the radiosonde data as the decline is inconsistent with theory. During the 1990 to 2001 period, upper atmosphere water vapor from satellite data declines more than that from radiosonde data, so there is no reason to dismiss the radiosonde data. Changes in water vapor are linked to temperature trends in the upper atmosphere. Both satellite data and radiosonde data confirm the absence of any tropical upper atmosphere temperature amplification, contrary to IPCC theory. Four independent data sets demonstrate that the IPCC theory is wrong. CO2 does not cause significant global warming.
Note 1. The NVAP data in Excel format is here.
Note 2.  The lower troposphere data is: http://www.nsstc.uah.edu/public/msu/t2lt/uahncdc.lt
The upper troposphere data is calculated as 1.1 x middle troposphere – 0.1 x lower stratosphere; where middle troposphere is: http://www.nsstc.uah.edu/public/msu/t2/uahncdc.mt and the lower stratosphere is:http://www.nsstc.uah.edu/public/msu/t4/uahncdc.ls

Sunday, February 2, 2014

New paper finds negative-feedback cooling from water vapor could almost completely offset warming from CO2

A new paper published in the Journal of Geophysical Research Atmospheres finds water vapor can act as a negative-feedback cooling effect to significantly counteract anthropogenic global warming. 

According to the paper, "The satellite observations have shown that warming of the tropical Indian Ocean and tropical Western Pacific Ocean -- with resulting increased precipitation and water vapor there -- causes the opposite effect of cooling in the tropical tropopause region above the warming sea surface. Once the tropical tropopause cools, less water vapor is present in the tropical tropopause and also above in the stratosphere,

Since water vapor is a very strong greenhouse gas, this effect leads to a negative feedback on climate change. That is, the increase in water vapor due to enhanced evaporation from the warming oceans is confined to the near- surface area, while the stratosphere becomes drier. Hence, this effect may actually slightly weaken the more dire forecasted aspects of an increasing warming of our climate, the scientists say."


The paper itself says, "In the lower stratosphere, the changes in water vapor and temperature due to projected future sea surface temperatures are of similar strength to, though slightly weaker than, that due directly to projected future CO2, ozone, and methane," which would indicate that this negative-feedback cooling effect is almost equivalent to the warming effect of man-made CO2, ozone, and methane and could almost fully offset global warming. 

The paper is similar to another recent paper published in Nature Climate Change, finding warming of sea surface temperatures in the Indian and Pacific Ocean 'warm pool' is causing less water vapor to enter the top of the troposphere and could cause global cooling from this negative-feedback. The papers add to many others finding water vapor acts as a negative-feedback, not positive as assumed by IPCC climate models. Climate model false assumptions of positive-feedback from water vapor are the entire basis of Mann-made global warming alarm. 



Nature can, selectively, buffer human-caused global warming, say scientists

February 2, 2014

Summary:


Can naturally occurring processes selectively buffer the full brunt of global warming caused by greenhouse gas emissions resulting from human activities? Yes, says a group of researchers in a new study.


As the globe warms, ocean temperatures rise, leading to increased water vapor escaping into the atmosphere. Water vapor is the most important greenhouse gas, and its impact on climate is amplified in the stratosphere.

Can naturally occurring processes selectively buffer the full brunt of global warming caused by greenhouse gas emissions resulting from human activities?

Yes, find researchers from the Hebrew University of Jerusalem, Johns Hopkins University in the US and NASA's Goddard Space Flight Center.

As the globe warms, ocean temperatures rise, leading to increased water vapor escaping into the atmosphere. Water vapor is the most important greenhouse gas, and its impact on climate is amplified in the stratosphere.

In a detailed study, the researchers from the three institutions examined the causes of changes in the temperatures and water vapor in the tropical tropopause layer (TTL). The TTL is a critical region of our atmosphere with characteristics of both the troposphere below and the stratosphere above.

The TTL can have significant influences on both atmospheric chemistry and climate, as its temperature determines how much water vapor can enter the stratosphere. Therefore, understanding any changes in the temperature of the TTL and what might be causing them is an important scientific question of significant societal relevance, say the researchers.

The Israeli and US scientists used measurements from satellite observations and output from chemistry-climate models to understand recent temperature trends in the TTL. Temperature measurements show where significant changes have taken place since 1979.

The satellite observations have shown that warming of the tropical Indian Ocean and tropical Western Pacific Ocean -- with resulting increased precipitation and water vapor there -- causes the opposite effect of cooling in the TTL region above the warming sea surface. Once the TTL cools, less water vapor is present in the TTL and also above in the stratosphere,

Since water vapor is a very strong greenhouse gas, this effect leads to a negative feedback on climate change. That is, the increase in water vapor due to enhanced evaporation from the warming oceans is confined to the near- surface area, while the stratosphere becomes drier. Hence, this effect may actually slightly weaken the more dire forecasted aspects of an increasing warming of our climate, the scientists say.
The researchers are Dr. Chaim Garfinkel of the Fredy and Nadine Herrmann Institute of Earth Sciences at the Hebrew University and formerly of Johns Hopkins University, Dr. D. W. Waugh and Dr. L. Wang of Johns Hopkins, and Dr. L. D. Oman and Dr. M. M. Hurwitz of the Goddard Space Flight Center. Their findings have been published in theJournal of Geophysical Research: Atmospheres, and the research was also highlighted in Nature Climate Change.

Story Source:

The above story is based on materials provided by Hebrew University of Jerusalem.Note: Materials may be edited for content and length.

Journal Reference:
C. I. Garfinkel, D. W. Waugh, L. D. Oman, L. Wang, M. M. Hurwitz. Temperature trends in the tropical upper troposphere and lower stratosphere: Connections with sea surface temperatures and implications for water vapor and ozone. Journal of Geophysical Research: Atmospheres, 2013; 118 (17): 9658 DOI: 10.1002/jgrd.50772



Temperature trends in the tropical upper troposphere and lower stratosphere: Connections with sea surface temperatures and implications for water vapor and ozone


C. I. Garfinkel1,2,*, D. W. Waugh1, L. D. Oman3, L. Wang1, M. M. Hurwitz3,4

Satellite observations and chemistry-climate model experiments are used to understand the zonal structure of tropical lower stratospheric temperature, water vapor, and ozone trends. The warming in the tropical upper troposphere over the past 30 years is strongest near the Indo-Pacific warm pool, while the warming trend in the western and central Pacific is much weaker. In the lower stratosphere, these trends are reversed: the historical cooling trend is strongest over the Indo-Pacific warm pool and is weakest in the western and central Pacific. These zonal variations are stronger than the zonal-mean response in boreal winter. Targeted experiments with a chemistry-climate model are used to demonstrate that sea surface temperature (hereafter SST) trends are driving the zonal asymmetry in upper tropospheric and lower stratospheric tropical temperature trends. Warming SSTs in the Indian Ocean and in the warm pool region have led to enhanced moist heating in the upper troposphere, and in turn to a Gill-like response that extends into the lower stratosphere. The anomalous circulation has led to zonal structure in the ozone and water vapor trends near the tropopause, and subsequently to less water vapor entering the stratosphere. The radiative impact of these changes in trace gases is smaller than the direct impact of the moist heating. Projected future SSTs appear to drive a temperature and water vapor response whose zonal structure is similar to the historical response. In the lower stratosphere, the changes in water vapor and temperature due to projected future SSTs are of similar strength to, though slightly weaker than, that due directly to projected future CO2, ozone, and methane.

Wednesday, November 19, 2014

Why water vapor slows cooling at night & slows warming during the day

Recent comments by physicist Daniel Sweger explain why water vapor/humidity slows cooling at night, and why water vapor has the opposite effect of slowing warming during the day. The comments relate to recent posts including "Modeling of the Earth’s Planetary Heat Balance with an Electrical Circuit Analogy," as well as posts from a few years ago (reposted below) discussing Dr. Sweger's analysis finding the correlation of humidity and temperature is clearly negative, and the effect of water vapor on climate is a net negative-feedback cooling effect:

Dr. Sweger: In this paper I compiled 2 years of data showing the relationship of both relative and absolute humidity and daily temperature in two different locations on the continent of Africa. In this paper I demonstrated that the correlation of humidity and temperature is clearly negative.

Reply: Humidity increases nighttime temperatures

Dr. Sweger: I agree, and for the same reason that during the day high humidity slows the increase in temperature. The reason is that heat energy only flows in one direction: from a higher to a lower temperature. It is the same as in an electrical circuit. Electricity only flows from a higher potential to a lower one. During the day the energy from the sun is flowing from the sun towards the surface of the earth. The high specific heat of water impedes the flow of heat in the same way as a higher value of a resistor impedes the flow of electrons. At night the situation is reversed. Now the heat energy is flowing away from the earth into a very cold space, and the presence of water vapor impedes the flow of heat energy away from the earth’s surface. Thus the surface temperature decreases less on a humid night than a dry night.

The purpose of the paper was to demonstrate that any feedback loop between the effect of “greenhouse gases” and the earth’s surface must be negative, since it would result in an increase in water vapor, and thus an increase in the impedance of heat flow.


Reposts of two prior HS posts on Dr. Sweger's analysis:

Tuesday, March 13, 2012 [REPOST]

Water vapor, not CO2, controls climate and acts as a negative feedback

Physicist Daniel Sweger refutes the catastrophic AGW hypothesis in his paper The Climate Engine, showing that CO2 has a negligible effect upon climate and that water vapor acts as a negative feedback to global warming. Dr. Sweger uses data from 3 locales to show an inverse relationship between humidity and temperature. He notes,
"In the positive feedback mechanism as proposed by the global warming proponents this behavior would be reversed. Then the data would show a positive relationship between moisture content and temperature. But it does not. As suggested before, data is the language of science, not mathematical models."

The data clearly shows that the relationship between the amount of water vapor in the air and temperature is negative 

From the conclusion of The Climate Engine:

The role of water vapor in determining  surface temperatures is ultimately a dominant one. During daylight hours it moderates the sun’s energy, at night it acts like a blanket to slow the loss of heat, and carries energy from the warm parts of the earth to the cold. Compared to that, if carbon dioxide has an effect, it must be negligible.

It is also clear from the data presented above that water vapor acts with a negative feedback. The data clearly shows that the relationship between the amount of water vapor in the air and temperature is negative; that is, the higher the amount of water vapor in the atmosphere the lower the surface temperature. In that regard, it almost acts as a thermostat.

As the air cools as a result of an increasing moisture content in the atmosphere, there is a decrease in the amount of water vapor produced by evaporation. Eventually this decrease of the level of water vapor being introduced into the atmosphere results in a decrease in moisture content. At this point more sunlight reaches the earth’s surface resulting in higher temperatures and increasing evaporation.

In the positive feedback mechanism as proposed by the global warming proponents this behavior would be reversed. Then  the data would show  a positive  relationship  between moisture  content and temperature. But it does not.

As suggested before, data is the language of science, not mathematical models.

About the Author:
Dr. Daniel M. Sweger, AB (Physics, Duke University, 1965) and Ph.D. (Solid State Physics, American University, 1974) has been a research scientist at NIST, where he was active in a variety of research areas, including cryogenic thermometry, solid state and nuclear physics, and molecular spectroscopy. He also operated a computer software business and performed  consulting for the US Army. He is now semi- retired and is an adjunct instructor at National College of Business and Technology (www.ncbt.edu), where, among other subjects, he teaches Environmental Science.

Saturday, April 2, 2011 [REPOST]

Physicist: Carbon dioxide has negligible effect on climate
Semi-retired physicist Dr. Daniel M. Sweger has been a research scientist at the National Institute of Standards and Technology, where he was active in a variety of research areas, including cryogenic thermometry, solid state and nuclear physics, and molecular spectroscopy.

Dr. Sweger's new paper, Earth’s Climate Engine (PDF), finds that if carbon dioxide has an effect on climate, it must be negligible. Instead, he finds on the basis of data and theory that water vapor is the dominant influence on climate, and its influence is the opposite of that assumed by the IPCC climate computer models.

From the Summary:
… While models can be useful, the results must be compared to actual measurements, i.e. data. Data is the language of science, but little has been done in that regard with the climate change models.

It is the premise of the author that water vapor is the dominant influence in determining and understanding global climate. Water vapor is much more abundant in the atmosphere than carbon dioxide, and its physical properties make it more important as well. During daylight hours it moderates the sun’s energy, at night it acts like a blanket to slow the loss of heat, and it carries energy from the warm parts of the earth to the cold. Compared to that, if carbon dioxide has any effect it must be negligible. Thus, the purpose of this paper is to explore the effect of water vapor on climate.

Detailed calculations and analysis of data from several locations clearly demonstrate that the effect of water vapor on temperature dominates any proposed effect of carbon dioxide. Furthermore, it is clear from the data presented that water vapor acts with a negative feedback on temperature, not a positive one. That is, the data demonstrate that increasing the level of water vapor in the atmosphere results in a decrease of temperature,not an increase as predicted by the climate models. In essence, atmospheric water vapor acts as a thermostat.

These results call into question the validity of using the results of the current general climate change models, particularly as the basis for policy decision making.
SOURCE

Related: Greenhouse Gases DO Have A Profound Effect On The Climate

Wednesday, November 5, 2014

New paper finds no long-term trend in stratospheric water vapor, IPCC claims opposite

A paper published today in the Journal of Geophysical Research Atmospheres by Andrew Dessler et al finds "little evidence for a long-term trend in water entering the stratosphere through the tropical tropopause layer over the past three decades."


And a 2010 paper by Susan Solomon et al is one [#7] of the 57 excuses for the 18+ year "pause" in global warming:
"Stratospheric water vapor concentrations decreased by about 10% after the year 2000. Here we show that this acted to slow the rate of increase in global surface temperature over 2000–2009 by about 25% compared to that which would have occurred due only to carbon dioxide and other greenhouse gases. More limited data suggest that stratospheric water vapor probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30% as compared to estimates neglecting this change. These findings show that stratospheric water vapor is an important driver of decadal global surface climate change."
In opposition, the modeling paper below shows increases of CO2 and water vapor in the stratosphere act as cooling agents, not warming agents, by increasing the radiative surface area to space.

So, take your pick of the settled science:
  • IPCC says there are long-term increases in stratospheric water vapor that are having a significant warming effect
  • Dessler says there is no long-term trend in stratospheric water vapor 
  • Solomon says decreased stratospheric water vapor is the cause for the "pause"
  • The modeling paper below finds increased stratospheric water vapor acts as a cooling, not warming, agent, contradicting the warming claims of the IPCC and Solomon. 
  • IPCC claims CO2 acts as the "control knob" of water vapor concentrations, but if that was true, there would not have been a 10% decrease in stratospheric water vapor 2000-2009 as claimed by Solomon above and there would be a long-term positive trend, not found by Dessler
  • Tropospheric water vapor has been on a long-term declining trend, and is the source of all stratospheric water vapor as noted by Dessler above. However, if tropospheric water vapor has declined, how could stratospheric water vapor increase 1980-2000 according to Solomon, or have a "long-term increase" according to the IPCC, or have no long-term trend according to Dessler?
All mutually exclusive, but certainly not unprecedented for the settled climate science

Excerpt from prior post:

3. Stratospheric cooling rates:  The picture shows how water, carbon dioxide and ozone contribute to longwave cooling in the stratosphere.   Colours from blue through red, yellow and to green show increasing cooling, grey areas show warming of the stratosphere.  The tropopause is shown as dotted line (the troposphere below and the stratosphere above).  For CO2 it is obvious that there is no cooling in the troposphere [or warming!], but a strong cooling effect in the stratosphere.  Ozone, on the other hand, cools the upper stratosphere but warms the lower stratosphere.  Figure from: Clough and Iacono, JGR, 1995; adapted from the SPARC Website.  Please click to enlarge! (60 K)  [Source] [Rebuttal] [Ozone O3 is shown as a cooling agent in the upper stratosphere, but a warming agent in the upper troposphere to lower stratosphere]
Note the scale at right side of graph indicates cooling rates and show water vapor is a cooling agent throughout the troposphere and stratosphere [only the brown colors indicate warming]. Also note that the computer-model output above demonstrates that CO2 is a very strong cooling agent in the stratosphere and CO2 is neither a cooling or warming agent of the troposphere [indicated by the light blue at the CO2 primary wavenumber at ~700 cm-1, or ~15um]. The modeled output shows CO2 to have a tiny blip of slight warming effect [light gray] at the tropopause [shown by dotted horizontal line], but clearly the net effect of CO2 shown in this diagram from the surface to the stratosphere is cooling, not warming.


Variations of stratospheric water vapor over the past three decades

A.E. Dessler et al

We examine variations in water vapor in air entering the stratosphere through the tropical tropopause layer (TTL) over the past three decades in satellite data and in a trajectory model. Most of the variance can be explained by three processes that affect the TTL: the quasi-biennial oscillation [which may be controlled by solar activity], the strength of the Brewer-Dobson circulation, and the temperature of the tropical troposphere. When these factors act in phase, significant variations in water entering the stratosphere are possible. We also find that volcanic eruptions, which inject aerosol into the TTL, affect the amount of water entering the stratosphere. While there is clear decadal variability in the data and models, we find little evidence for a long-term trend in water entering the stratosphere through the TTL [tropical tropopause layer] over the past 3 decades.