## Planetary Energy Imbalance

I’m on a train heading to a meeting, and so, to move on from the whole Brexit saga, I thought I would briefly highlight this recent paper that provides an [Improved] estimate of Earth’s energy imbalance. It uses ocean heat content measurements from Argo floats, and corrects for the very deep ocean, land and atmosphere, and cryosphere warming. It also shows CERES satellite measurements, which have been corrected to agree with the mean of in situ estimates for the period 2005-2010.

Credit : Johnson, Lyman & Loeb (2016)

The bottom line is that for the period 2005-2015, the net heat uptake rate was $0.71 \pm 0.1$ Wm-2. To put this into somce context, this is just over 1022J per year, which – if it all remained in the land/atmosphere – would warm the land/atmosphere at more then 1oC per year. Of course, it does not all heat the land/atmosphere, as most (> 90%) heats the oceans. However, this is still one of the key indicators that we are undergoing anthropogenic global warming (the climate system as a whole is continuing to accrue energy, even as we continue to warm).

The only other thing I was going to mention is that this doesn’t really change the Otto et al. (2013) energy balance estimates for the Effective Climate Sensitivity (~ 2oC), but does – I think – influence the Lewis & Curry (2015) estimates (~ 1.66oC) as they used heat uptake rates that were quite a bit lower than this newer estimate suggests. I think this also has implications for the TCR-to-ECS ratio, but I’ll leave it at that, as I have to get off the train in a short while.

This entry was posted in Climate change, Climate sensitivity, Global warming, Science and tagged , , , , , , , . Bookmark the permalink.

### 40 Responses to Planetary Energy Imbalance

1. BBD says:

I wonder how long it will take before NL finds ‘schoolboy errors’ in this and demands that it be withdrawn.

In due seriousness though, both interesting and unsurprising.

2. I think it’s going to get harder and harder for Nic Lewis to continue promoting his low CS values. Do we really think that the TCR can be less than 1.4oC? That would seem to require continued slow surface warming, which seems unlikely. Do we really think that the TCR-to-ECS ratio can be above 0.8? This result here would – I think – suggest not. So, a TCR above 1.4oC and a TCR-to-ECE ration below 0.8. and we’re right back in 2oC territory for the ECS.

3. Magma says:

We previously estimated the EEI [from 2005 to 2010] at 0.58 ± 0.38 W m-2… we update our calculations (Fig. 1), and find a net heat uptake of 0.71 ± 0.10 W m-2 from 2005 to 2015

Considering two binary end-member options, that
A) Lewis and Curry originally cherry-picked the lowest values of global heat uptake they could find in the literature to derive a low ECS value or
B) the vast warmist conspiracy finally got to authors Johnson, Lyman and Loeb, possibly by threatening their grants, careers, families or lives…

it goes without saying that the only sane* answer is B.

4. It also shows CERES satellite measurements, which have been corrected to agree with the mean of in situ estimates for the period 2005-2010.

Was there an actual correction to CERES processing?

5. JCH says:

Lewis and Curry is warmed over Girma. The trend 2001 through 2020 is going to meet, maybe even exceed, .2 ℃ per decade.

6. TE,
I don’t really know what you’re asking. As I understand it, the variance in the CERES data is not adjusted, simply the mean to match that of the in situ measurements.

7. Quite possibly, and if you expect around 2% of the planetary energy imbalance to heat the land/atmosphere, that’s what you’d expect for an imbalance of around 0.7 W/m^2.

LC14 used 0.15w/m2 in the initial period for heat uptake, with an increase between periods of 0.36 – so a heat uptake of 0.51 in the end period. It’s table 3 in the paper. Their method for the starting period was taking the 0.25w/m2 produced by a climate model and downscaling to 2/3 this figure because that model had a sensitivity of about 3C. Not sure if this downscaling makes physical sense, but there aren’t measurements for heat uptake from the era anyway so…

0.51 is lower than this paper finds, but then the final period in LC14 was 1995-2011 not 2005-2015. Lewis reported in the last update that extending the period to the present (1995-2015) drives the change in uptake to 0.48w/m2, implying 0.63 uptake in the end period; this is essentially in line with the 0.71 this paper reports (because uptake was lower in 1995-2004). It also moves the main ECS result to 1.74C, rather than the 1.67C found in the original paper.
https://judithcurry.com/2016/04/25/updated-climate-sensitivity-estimates/

Anyway, if the increase in heat uptake was 0.63, i.e. assuming there was zero uptake in the starting period (which is absurd), the result wouldn’t change that much:
0.75C x (3.7w/m2 / (2.07 – 0.63)w/m2) = 1.93C

One could also do the numbers with a an uptake increase of 0.7w/m2 but then one would have to use the forcings and temperature increase for 2005-2015 and my climate fu isn’t there.

9. Ethan Allen says:

Their previous estimate was for the period 2005-2010 (six years). Their current estimate is for the period 2005-2015 inclusive (eleven years). (at least that’s how I read these things as end years inclusive)

They report R = 0.76 (R^2 = 0.61) between CERES and EEI. The word “corrected” does not appear in this technical note.

“It was used to anchor satellite-observed EEI from the Clouds and the Earth’s Radiant Energy System (CERES), which, although stable over time, is not sufficiently accurate in absolute value to determine EEI at the required level.”
Moving means (constant linear offsets) does not affect slope or R^2 for linear models (y = ax +b).

10. Ethan Allen says:

“0.76” should be “0.78” above 😦

11. Alberto,
I did try to rerun the numbers and if you do so, you a result similar to that in Ottoman et al. and, hence, higher than in Lewis & Curry. Of course, this ignores uncertainties etc.

12. JCH says:

Ottoman et al… is that seepage from the get/keep the Ottomans Out thread?

13. Kristian says:

ATTP, you claim in your top post:

(…) this is still one of the key indicators that we are undergoing anthropogenic global warming (the climate system as a whole is continuing to accrue energy, even as we continue to warm).

Er, no. Quite the opposite. This is one of the key indicators that we are not undergoing ‘anthropogenic’ global warming, but rather a completely natural global warming. Because the imbalance was specifically caused by an increase in ASR and not by a reduction in OLR:

14. MartinM says:

Because the imbalance was specifically caused by an increase in ASR and not by a reduction in OLR

You say ‘because’, but there’s no actual relationship between this and the conclusion you derive from it.

15. JCH says:

MartinM – where did you get the quote?

Because the imbalance was specifically caused by an increase in ASR and not by a reduction in OLR

16. Sorry, I was trying to avoid posting Kristians’s comment till I had a chance to respond, but I didn’t moderate fast enough. It’s out now. I’ll respond properly later.

17. izen says:

This –
http://www.climate-lab-book.ac.uk/2016/reconciling-estimates-of-climate-sensitivity/
Seems to be discussing another factor that reduces the uncertainty on TCR sensitivity estimates. Or at least shifts the probabilities away from the bottom of the range.

Kristian’s graphs certainly show the impact of Pinatubo, but look a bit too noisy to be sure of small long term trends. If there is a shift in ASR then as insolation has not increased an albedo change could be responsible. Not good news if that is a sign of cloud, snow/ice changes, then it is more likley a positive feedback from AGW than a completely natural global warming.
Anyone know the provenance of the graphs, and the original context of the data?

18. Magma says:

@ izen: They’re from NASA’s ISCCP (International Satellite Cloud Climatology Project) page. I’m not familiar enough with the data to even offer a summary.

http://isccp.giss.nasa.gov/projects/browse_fc.html

19. JCH says:
20. Olof R says:

A global net heat uptake of 0.71 W/m2 for 2005-2015 seems like a relatively low etstimate.
According to NOAA/ NODC the OHC in the 0-2000 m layer has increased by 12.23*10^22 J between 2005 and 2015, which equals 0.76 W/m2. To that should be added warming below 2000 m, warming of atmosphere, ground, melting of ice, etc, which makes a total heat uptake of more than 0.9 W/m2 likely..

21. izen says:

@- JCH
The “Shortwave and longwave radiative contributions to
global warming under increasing CO2″ helps.

So out-going LWR equalibriates fast if the feedbacks on albedo via clouds and snow cover are fast. Makes sense.

Meanwhile the graphs that Kristian posted seem to be cherry-picked in terms of dates and fluxes and omit the page of caveats that come with the originals explaining that –
” Although some smaller magnitude features may be realistic, the larger variations are likely to be spurious (except for the Pinatubo decrease). The total net fluxes in the atmosphere (positive values imply heating) are also mostly distorted by the spurious changes in the atmospheric temperature dataset.”

I am always puzzled why dragon slayers seem to think that it would be good news that the observed warming is “a completely natural global warming”. If that were true and the albedo shift IS due to some as yet undiscovered and unsuspected ‘natural’ change then what is its limit?

Some years ago I had a futile discussion with Bob Tisdale who I see from HotWopper is still pushing his ‘warming is caused by an ENSO rachet’ theory. I pointed out that this was extremely worrying because there is no known upper limit to the warming coming from such an unknown ‘natural’ source. At least with AGW there is some promise that the magnitude of warming is limited and open to human intervention. Apparently magical processes will stop and reverse the ‘natural’ trend at some unspecified time for some unspecified reason.

If ENSO or ‘completely natural’ albedo changes can trend surface temperature by >1 degC per century then in in less time than since the fall of Rome, most of the surface is beyond biological tolerance. Unless you can explain what ‘completely natural’ process is causing it and why it has an upper limit the hypothesis implies a major extinction of most life on Earth within the next millennia.

22. Olof,
I thought they had compensated for all of that.

23. BBD says:

WRT Kristian’s misrepresentation of ISCCP, see Evan et al. (2007), emphasis mine:

The International Satellite Cloud Climatology Project (ISCCP) multi-decadal record of cloudiness exhibits a well-known global decrease in cloud amounts. This downward trend has recently been used to suggest widespread increases in surface solar heating, decreases in planetary albedo, and deficiencies in global climate models. Here we show that trends observed in the ISCCP data are satellite viewing geometry artifacts and are not related to physical changes in the atmosphere. Our results suggest that in its current form, the ISCCP data may not be appropriate for certain long-term global studies, especially those focused on trends.

24. Kristian says:

BBD. Did you notice the dashed curve accompanying the solid ISCCP FD curve in the three plots? That’s ERBS Ed3. It is not the Ed3_Rev1, which shows lower, but still significant trends:

25. Kristian,
Unless I’m mistaken, you essentially deny the fundamentals of the basic greenhouse effect. If so, I can’t imagine that there is much point in taking this any further.

26. Kristian says:

JCH,

Two things worth noting about ‘Donohoe et al., 2014’:

1) They explicitly state that the current ToA imbalance is assumed to be caused by reduced OLR (-0.8 W/m^2) and rather countered slightly by reduced ASR (-0.2 W/m^2). Their model results discuss FUTURE scenarios, with about 0.5K of extra global warming, not the current situation. IOW, they do not at all describe the real world, only a hypothetical (model) future world.

2) Their hypothetical future increase in ASR is explicitly stated NOT to involve cloud cover (that is assumed constant). Again this is contrary to the real world situation …

27. Kristian says:

Kristian,
Unless I’m mistaken, you essentially deny the fundamentals of the basic greenhouse effect. If so, I can’t imagine that there is much point in taking this any further.

If you don’t want to discuss the data presented, then I’m fine with that …

28. Kristian,
I can’t see much point in discussing the data presented if there isn’t agreement about the relevant fundamentals.

29. BBD says:

In other words, ‘satellites disprove physics’ arguments are a waste of time.

30. izen says:

@- Kristian
Two things worth noting about ‘Donohoe et al., 2014’:
“1) They explicitly state that the current ToA imbalance is assumed to be caused by reduced OLR (-0.8 W/m^2) and rather countered slightly by reduced ASR (-0.2 W/m^2).”

Are you sure you are reading the correct paper? The version I see explicitly states that the OLR is first expected to reduce, then re-equiliberate. The modelling indicates this can happen within 2 decades as positive feedbacks act to alter the ASR. Observational data also indicates this happens, although as they state –
“the limited length of satellite TOA radiation
measurements precludes determination of the relative contributions
of ASR and OLR by direct observation.”

@-“2) Their hypothetical future increase in ASR is explicitly stated NOT to involve cloud cover (that is assumed constant). Again this is contrary to the real world situation …”

Actually they state that the positive feedback effect that means warming from increased GHG is caused most by ASR is generated without any cloud changes. Humidity, snow and ice cover changes are sufficient. Changes with strong observational backing.
In the real world there is no clear evidence for any significant change in cloud cover. As has already been mentioned the satellite data is too short and distorted by ignoring the fact that clouds are 3-dimensional and observations were not adjusted for angle of view.

So you are claiming that the warming must be natural because of a satellite result that is known to be uncertain, but a result that is entirely consistent with model and observational understanding of how warming from increased GHG is expressed in the atmosphere.
Now what is it about the data you want to discuss, or are you just going to erroneously claim it indicates that GHG are not the cause of warming when the data, such as it is with the inherent uncertainty, is generally taken to CONFIRM the role of rising CO2?

31. BBD says:

If you don’t want to discuss the data presented, then I’m fine with that …

The available data sets are not sufficiently robust to support strong claims. End of data discussion.

Analyses of the spatial trends in ISCCP cloud cover reveal changing biases arising from changes in satellite view angle and coverage that affect the global mean anomaly time series (Norris, 2000; Dai et al., 2006). The ISCCP spurious variability may occur primarily in low-level clouds with the least optical thickness (the ISCCP ‘cumulus’ category; Norris, 2005a), due to discontinuities in satellite view angles associated with changes in satellites. Such biases likely contribute to ISCCP’s negative cloud cover trend, although their magnitude and impact on radiative flux calculations using ISCCP cloud data are not yet known. Additional artefacts, including radiometric noise, navigation and rectification errors are present in the ISCCP data (Norris, 2000), but the effects of known and unknown artefacts on ISCCP cloud and flux data have not yet been quantified.

Other satellite data sets show conflicting decadal changes in total cloud cover. For example, analysis of cloud cover changes from the HIRS shows a slight increase in cloud cover between 1985 and 2001 (Wylie et al., 2005). However, spurious changes have also been identified in the HIRS data set, which may affect its estimates of decadal variability. One important source of uncertainty results from the drift in Equatorial Crossing Time (ECT) of polar-orbiting satellite measurements (e.g., HIRS and the Advanced Very High Resolution Radiometer; AVHRR), which aliases the large diurnal cycle of clouds into spurious lower-frequency variations. After correcting for ECT drift and other small calibration errors in AVHRR measurements of cloudiness, Jacobowitz et al. (2003) found essentially no trend in cloud cover for the tropics from 1981 to 2000.

While the variability in surface-observed upper-level cloud cover has been shown to be consistent with that observed by ISCCP (Norris, 2005a), the variability in total cloud cover is not, implying differences between ISCCP and surface-observed low cloud cover. Norris (2005a) shows that even after taking into account the difference between surface and satellite views of low-level clouds, the decadal changes between the ISCCP and surface data sets still disagree. The extent to which this results from differences in spatial and temporal sampling or differences in viewing perspective is unclear.

In summary, while there is some consistency between ISCCP, ERBS, SAGE II and surface observations of a reduction in high cloud cover during the 1990s relative to the 1980s, there are substantial uncertainties in decadal trends in all data sets and at present there is no clear consensus on changes in total cloudiness over decadal time scales.

32. izen says:

@- BBD
“In other words, ‘satellites disprove physics’ arguments are a waste of time.”

one of the most ironic thing about arguments against AGW using satellite data is that most of that data derives from very precise knowledge – and modelling – of how energy is absorbed and propagated within the atmosphere.
It always seems somewhat paradoxical to be arguing that the greenhouse effect does not exist from data that is rooted in HITRANS/MODTRANS understanding of just that energy absorption/re-admission process.

33. BBD says:

Irrational zombies 🙂

34. Steven Mosher says:

“It always seems somewhat paradoxical to be arguing that the greenhouse effect does not exist from data that is rooted in HITRANS/MODTRANS understanding of just that energy absorption/re-admission process.”

their heads generally explode when you mention this.

35. BBD says:

They shouldn’t. It’s cheating; it breaks the Romero Directive.

36. one of the most ironic thing about arguments against AGW using satellite data

Hmmm… there has been warming, so it’s not so much a case that satellite TOA radiance estimates contradict warming. Rather, satellite estimates are not inconsistent with observed warming being enough to have restored equilibrium. Of course, satellite estimates have quite a lot of uncertainty, so they’re also not inconsistent with there being an imbalance taken up at the BOA ( Bottom Of the Atmosphere, that is, the ocean, which OHC indicates ).

By virtue of the fact that OHC is based on in situ measurement as opposed to passive remote obs, there probably is more confidence in OHC than orbitting satellite. However, there are still uncertainties about OHC estimates.

37. JCH says:
38. BBD says:

Reanimated…

This site uses Akismet to reduce spam. Learn how your comment data is processed.