Forgetting the theory for a moment, it is easy to relate
the observed change in surface temperature to the sort of observed change in atmospheric CO2 from 1850 to today, assuming
Consistent with
observed changes in surface temperature, there has been an almost worldwide reduction in glacier and small ice cap (not including Antarctica and Greenland) mass and extent in the 20th century; snow cover has decreased in many regions of the Northern Hemisphere; sea ice extents have decreased in the Arctic, particularly in spring and summer (Chapter 4); the oceans are warming; and sea level is rising (Chapter 5).
Not exact matches
The map below shows the
observed change in global near -
surface air
temperature since 1900.
Taking factors such as sea
surface temperature, greenhouse gases and natural aerosol particles into consideration, the researchers determined that
changes in the concentration of black carbon could be the primary driving force behind the
observed alterations to the hydrological cycle
in the region.
That study addressed a puzzle, namely that recent studies using the
observed changes in Earth's
surface temperature suggested climate sensitivity is likely towards the lower end of the estimated range.
This is not only
in excellent agreement with the
observed temperature changes at the
surface (blue stars), it also correctly reproduces the
observed heat storage
in the oceans — a strong indicator that the model's heat budget is correct.
«
In this post we will evaluate this contrarian claim by comparing the global
surface temperature projections from each of the first four IPCC reports to the subsequent
observed temperature changes.
That illustrates my point, which is that present
changes in surface temperature is not a good indicator of what we should expect
in the future, and as such, it is not a great idea to make the debate about the
observed ocean
temperature.
The problem here is that estimates of
changes in sea
surface temperature and the depth of the warm mixed layer might be very unreliable, since the general behavior of the Atlantic circulation is only now being directly
observed — and the most recent findings are that flow rates vary over a whole order of magnitude:
The significant difference between the
observed decrease of the CO2 sink estimated by the inversion (0.03 PgC / y per decade) and the expected increase due solely to rising atmospheric CO2 -LRB--0.05 PgC / y per decade) indicates that there has been a relative weakening of the Southern Ocean CO2 sink (0.08 PgC / y per decade) due to
changes in other atmospheric forcing (winds,
surface air
temperature, and water fluxes).
«
In this post we will evaluate this contrarian claim by comparing the global
surface temperature projections from each of the first four IPCC reports to the subsequent
observed temperature changes.
This is not only
in excellent agreement with the
observed temperature changes at the
surface (blue stars), it also correctly reproduces the
observed heat storage
in the oceans — a strong indicator that the model's heat budget is correct.
That study addressed a puzzle, namely that recent studies using the
observed changes in Earth's
surface temperature suggested climate sensitivity is likely towards the lower end of the estimated range.
The basic issue is that nudging
surface temperatures in the North Atlantic closer to
observed data would probably nudge the Atlantic overturning circulation
in the wrong direction since
changing the
temperature without
changing the salinity will give the opposite buoyancy forcing to what would be needed.
Now that I have answered your challenge to the question
in your original post, you have
changed the question to «'' No one calculates the
surface temperature (which is well
observed) using the atmospheric heat content».
Here we would like to try to distinguish between warming
in the nocturnal boundary layer due to a redistribution of heat and warming due to the accumulation of heat... It is likely that the
observed warming
in minimum
temperature, whether caused by additional greenhouse forcing or land use
changes or other land
surface dynamics, is reflecting a redistribution of heat by turbulence - not an accumulation of heat.
In this work the equilibrium climate sensitivity (ECS) is estimated based on observed near - surface temperature change from the instrumental record, changes in ocean heat content and detailed RF time serie
In this work the equilibrium climate sensitivity (ECS) is estimated based on
observed near -
surface temperature change from the instrumental record,
changes in ocean heat content and detailed RF time serie
in ocean heat content and detailed RF time series.
In 2013, the Intergovernmental Panel on Climate Change Fifth Assessment Report stated a clear expert consensus that: «It is extremely likely [defined as 95 - 100 % certainty] that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic [human - caused] increase in greenhouse gas concentrations and other anthropogenic forcings together.&raqu
In 2013, the Intergovernmental Panel on Climate
Change Fifth Assessment Report stated a clear expert consensus that: «It is extremely likely [defined as 95 - 100 % certainty] that more than half of the
observed increase
in global average surface temperature from 1951 to 2010 was caused by the anthropogenic [human - caused] increase in greenhouse gas concentrations and other anthropogenic forcings together.&raqu
in global average
surface temperature from 1951 to 2010 was caused by the anthropogenic [human - caused] increase
in greenhouse gas concentrations and other anthropogenic forcings together.&raqu
in greenhouse gas concentrations and other anthropogenic forcings together.»
Note: The step
change (
temperature drop) at 1945 has been identified as an error in a recent Thompson et al letter to «Nature» with the title «A Large Discontinuity in the Mid-Twentieth Century in Observed Global - Mean Surface Temperat
temperature drop) at 1945 has been identified as an error
in a recent Thompson et al letter to «Nature» with the title «A Large Discontinuity
in the Mid-Twentieth Century
in Observed Global - Mean
Surface TemperatureTemperature».
By comparing modelled and
observed changes in such indices, which include the global mean
surface temperature, the land - ocean
temperature contrast, the
temperature contrast between the NH and SH, the mean magnitude of the annual cycle
in temperature over land and the mean meridional
temperature gradient
in the NH mid-latitudes, Braganza et al. (2004) estimate that anthropogenic forcing accounts for almost all of the warming
observed between 1946 and 1995 whereas warming between 1896 and 1945 is explained by a combination of anthropogenic and natural forcing and internal variability.
What's lost
in a lot of the discussion about human - caused climate
change is not that the sum of human activities is leading to some warming of the earth's
temperature, but that the
observed rate of warming (both at the earth's
surface and throughout the lower atmosphere) is considerably less than has been anticipated by the collection of climate models upon whose projections climate alarm (i.e., justification for strict restrictions on the use of fossil fuels) is built.
After accounting for volcanic and human effects, the residual variability
in land -
surface temperature is
observed to closely mirror (and for slower
changes slightly lead) variations
in the Gulf Stream.
Many variables — rainfall, sea
surface temperature, fisheries, cyclone frequency — all are
observed in empirical evidence — hard data — to
change abruptly and for lessor or longer periods.
Here we show that accounting for recent cooling
in the eastern equatorial Pacific reconciles climate simulations and observations.We present a novel method of uncovering mechanisms for global
temperature change by prescribing,
in addition to radiative forcing, the
observed history of sea
surface temperature over the central to eastern tropical Pacific
in a climate model.
After all, the TCR is associated with the
temperature change in response to increasing CO2, and Gillett et al. attribute essentially the entire
observed global
surface warming to the greenhouse gas increase.
«Global warming, which is a part of climate
change, is the
observed increase
in average
temperature of the Earth's
surface and atmosphere.
We conclude by underlining that the
observed variation of glacier
surface and SLA
changes could be explained by the increase of
temperature and decrease of precipitation
in recent years.
Ozone depletion
in the late twentieth century was the primary driver of the
observed poleward shift of the jet during summer, which has been linked to
changes in tropospheric and
surface temperatures, clouds and cloud radiative effects, and precipitation at both middle and low latitudes.
Even while identifying some of the
observed change in climatic behaviour, such as a 0.4 C increase
in surface temperature over the past century, or about 1 mm per year sea level rise
in Northern Indian Ocean, or wider variation
in rainfall patterns, the document notes that no firm link between the do...
That suggests that the 1940s tropical warming could have started the
changes in the Amundsen Sea ice shelves that are being
observed now... He emphasized that natural variations
in tropical sea -
surface temperatures associated with the El Niño Southern Oscillation play a significant role.»
First row: trends
in observed temperature changes (Hadley Centre / Climatic Research Unit gridded
surface temperature data set (HadCRUT3), Brohan et al., 2006).
By figuring out the exact thermal transfer rate as you go downward
in the strata being measured and taking an exact
temperature measurement along the way
surface temperature changes in the past can be
observed.
I should not be surprised if,
in due course, the Professor were to publish a paper on the implications of the remarkably substantial discrepancy between the model - predicted and actually -
observed rates of
change in surface evaporation per unit
change in surface temperature.
In his House of Commons presentation, toward the end, he gives a sketch of an alternative derivation of the «Climate Sensitivity» based on observed rates of evaporation increase per change in sea surface temperature, and this based on data from the 2007 paper by Wentz e
In his House of Commons presentation, toward the end, he gives a sketch of an alternative derivation of the «Climate Sensitivity» based on
observed rates of evaporation increase per
change in sea surface temperature, and this based on data from the 2007 paper by Wentz e
in sea
surface temperature, and this based on data from the 2007 paper by Wentz et.
Hence, the panel concludes that at least part of the
observed disparity between the 20 - year
changes in surface and mid-tropospheric
temperature is probably real, but the measurement, modeling, and sampling uncertainties alluded to above make it difficult to precisely attribute the disparity to any particular sources.
Observed changes in (a) global average
surface temperature; (b) global average sea level rise from tide gauge (blue) and satellite (red) data and (c) Northern Hemisphere snow cover for March - April.
The new research uses multiple runs of a coupled ocean - atmosphere computer model to simulate global
temperature changes in response to climate forcing when the sea
surface temperature (SST)
in the el Niño region follows its historically
observed values.
This combined evidence... is substantially stronger than the evidence that is available from
observed changes in global
surface temperature alone.
The discrepancy between recent
observed and simulated trends
in global mean
surface temperature has provoked a debate about possible causes and implications for future climate
change projections.
Finds that average daytime
surface temperature in the Jambi province increased by 1.05 °C over the last 16 years, which followed the trend of
observed land cover
changes and exceeded the effects of climate warming
There is consistence [70] between the estimates of the ISCCP, the global albedo, the insolation measured at the
surface and the length of the daily insolation
observed in many places: all of them are likely to explain the
temperature changes.
Wardle and Smith (2004) argued that the upward rainfall trend is consistent with the upward trend
in land
surface temperatures that has been
observed in the south of the continent, independent of
changes over the oceans.
If there is deep - water formation
in the final steady state as
in the present day, the ocean will eventually warm up fairly uniformly by the amount of the global average
surface temperature change (Stouffer and Manabe, 2003), which would result
in about 0.5 m of thermal expansion per degree celsius of warming, calculated from
observed climatology; the EMICs
in Figure 10.34 indicate 0.2 to 0.6 m °C — 1 for their final steady state (year 3000) relative to 2000.
Well, I was one of the first persons
in the blogosphere at the time to evaluate that, because I compared the dip
in the
temperature of sampled water with the dip
in the
temperature of near -
surface air measured on ships, and
observed that approximately half or so of the dip was explainable by instrumentation
changes and the remainder by some other mechanism — probably a
change in internal ocean dynamics (PDO, AMO, etc..)
We can all
observe the greening that more atmospheric CO2 brings, but this greening is unlikely to result
in measurable
surface temperature change.
As expected, the ability of the model to simulate
observed changes in global
surface temperature after 1998 improves as less reliable observations from the early portion of the sample period are eliminated from the estimation sample (Fig. 2).
Global
temperature change obtained by multiplying the sum of the two climate forcings
in figure 5c by a sensitivity of 3/4 °C per W m − 2 yields a remarkably good fit to «observations» (figure 6), where the
observed temperature is 2 × ΔTdo, with 2 being the scale factor required to yield the estimated 4.5 °C LGM — Holocene
surface temperature change.
Soloman and her co-authors argue that El Niño has been one of the drivers of
changes in stratospheric water vapor, noting that «The drop
in stratospheric water vapor
observed after 2001 has been correlated to sea
surface temperature (SST) increases
in the vicinity of the tropical «warm pool» which are related to the El Niño Southern Oscillation (ENSO).»
In it, they documented how a change in observing practices before and after World War II produced a cold bias in the sea surface temperatures that were incorporated into the compilations of global average temperatures (see here and here for more details
In it, they documented how a
change in observing practices before and after World War II produced a cold bias in the sea surface temperatures that were incorporated into the compilations of global average temperatures (see here and here for more details
in observing practices before and after World War II produced a cold bias
in the sea surface temperatures that were incorporated into the compilations of global average temperatures (see here and here for more details
in the sea
surface temperatures that were incorporated into the compilations of global average
temperatures (see here and here for more details).
Observed temperature (black line), the out - of - sample forecast for global
surface temperature driven by anthropogenic
changes in radiative forcing (red line) and the out - of - sample forecast for global
surface temperature driven by natural variables (solar insolation, SOI, and volcanic sulfates)(green line).