NASA has at least four satellites measuring key climatic data:
- Sea ice
- Snow cover
In this post the NASA satellite data is reviewed and what it tells us about climate change is evaluated.
The image shows how global cloud cover has evolved with time at various latitudes since 1983 (to the left). Just one of the amazing data sets acquired by NASA but buried by the IPCC because it does not obey the global warming story line.
Troposphere and stratosphere temperature is measured indirectly using microwave radiation as measured by a number of different orbiting satellites. Two different research groups analyse the data – Roy Spencer at the University of Huntsville Alabama and Remote Sensing Systems. Those readers who follow Roy will be familiar with the chart below that he updates every month (Figure 1). There are two ways to view this data. The first is to take the view that cyclically variable temperatures have been rising slowly for the 36 years of the satellite record with an overall rise of about 0.5˚C in that time, translating to 1.4˚C per century. The second view, which is the one I actually prefer, is that 1998 is a marker event with the big el Nino. Temperatures prior to that were cyclical but with a flat trend. And temperatures after 1998 are also cyclical with a flat trend – the famous pause, as illustrated in Figure 2.
Figure 1 The view of surface temperatures from space as constructed and published by Dr Roy Spencer of the University of Alabama.
Figure 2 Detail of the same satellite temperature data for the last 18 years and 3 months of the great pause, this time using the RSS algorithms and as compiled by Christopher Monckton.
Roy Spencer’s analysis of the annual means of the satellite temperatures shows that 2014 had a mean anomaly of +0.27˚C and was the third warmest, not the warmest year on record.
This begs the question why NASA chose to report to President Obama what appear to be doctored data from the surface thermometer record in preference to using their own satellite data that has much more uniform global coverage and is likely superior quality.
The International Satellite Cloud Climatology Project (ISCCP) is also administered by NASA. I happened upon a rare published chart in 2013 that showed temporal variance in global D2 cloud cover that seemed to mirror temperature variance. The ISCCP data begin in July 1983 and while data is still being acquired, the released data stopped in December 2008 at the time I downloaded it.
Figure 3 ISCCP global mean cloud amount in black varies inversely with temperature in blue. No major surprise there, less cloud and a warmer surface, but what causes what? Chart from Clive Best.
NASA provide the files in .csv format and also provide a handy application called Panoply that allows you to read the file and make great graphics like the one below. Handling this data was beyond my capabilities and I therefore recruited assistance from Clive Best who produced the chart above. What we see are cyclical changes in cloud amount and from month 30 to 190 a decline in the amount of global cloud cover. Thereafter the amount of cloud stabilises and perhaps starts to rise slowly. Month 190 = 1999, the year after the great El Nino and climate watchers will know that this also marks the beginning of the great pause (Figure 2). Clive has also plotted HadCRUT4 and it can be seen that global average temperatures mirror global average cloud cover. The simplest explanation is that temporal changes in cloud give rise to temporal changes in surface temperatures, but not everyone agrees, perhaps it is vice versa.
Figure 4 Panoply time series plot of global cloud cover. To the extent that cloud cover controls sunshine and rainfall this image presents one of the clearest pictures on how climate has changed since 1983. There is no evidence that increasing CO2 is influencing this natural rhythm. Rather than trying to explain this marvellous data, the IPCC have simply called its veracity into question and then proceeded to ignore it much to the chagrin of the NASA scientists involved (see below).
The above graphic, made using Panoply, illustrates a time series beginning at June 1983 to the left and ending June 2008 to the right. The Y-axis are lines of latitude, North Pole at top South Pole at bottom. Reading along the lines of latitude reveals some interesting trends. Between 0 and 30˚ N it is quite clear that cloud cover has reduced with time. This would result in higher temperatures and less rainfall, not everywhere in that belt, but those affected will most certainly experience climate change, probably adverse. This belt encompasses Central America, Northern Africa and India. A similar though less marked trend is evident between 0 and 30˚ S. The line 60˚ S has the highest amount of cloud and it is probably no coincidence that it makes no landfall running through the Southern Ocean. 90% cloud cover would be rather depressing. In 1983, the amount of cloud in this belt begins high, it then declines before increasing again after 1998.
Much of the developed worlds population lives between 30 and 60˚ N and you can see that there has not been much going on there. One possible exception is just N of 30˚since 1998 the cyclical low summer cloud amount has been stretching further N (these blue bumps above the 30˚ line). This I imagine may be a graphic explanation of drought in SW California.
So what does this tell us about climate change? I find it difficult to see anything other than a natural rhythm in this data, perhaps underpinned by shifting ocean currents and climatic cycles such as the PDO and AMO. The IPCC do not like the negative correlation between cloud and temperatures and therefore call the veracity of the data into question and sweep this amazing data set under the carpet. Here’s what they had to say:
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.
Can cyclical change in cloud explain all surface temperature variance? Well the answer is no. Clive Best deduced, using some pretty fancy physics, that a CO2 forcing was also required to explain part of the temperature trend with a transient climate response (TCR) = 1.6±0.3˚C. In the partner study to this we looked at variance in UK cloud cover and temperature and deduced a TCR = 1.28˚C. Myself and Clive are not “deniers” we simply share the view that the balance of evidence points to a low value for TCR, see little evidence for extreme feedbacks, and see no urgent need to shut down the global fossil fuel industries and industrial civilisation with it.
The University of Illinois is the curator of the NASA / NSIDC global sea ice data that is accessible through the well known website Cryosphere Today. They present the data in a number of charts and maps. Here I will reproduce just three of these: Arctic sea ice area, Antarctic sea ice area and a composite global sea ice area and anomaly.
Figure 5 Northern hemisphere sea ice area. The mid-winter highs have been descending slowly since records began, the mid summer lows descending somewhat faster with a sudden acceleration in 2007. There is nothing to suggest that this is not part of a natural cycle. The late John Daly gives a good account and explains why variable ocean currents are the most likely cause of Arctic Sea Ice loss. Note the article dates from around 2000.
Figure 6 Antarctic sea ice area has been stable / slowly rising since 1979 with most marked increase in recent years, 2014 setting a new satellite era record high.
Figure 7 The Arctic and Antarctic sea ice cycles are not in perfect anti-phase giving rise to the two topped pattern. The sea ice maximum in the Arctic occurs in March each year, in the Antarctic in September. The peaks are six months apart. The lower red line shows the global sea ice anomaly. The five major Arctic melt back years starting in 2007 are clearly visible. Equally visible is the fact that that process appears to have reversed and the global anomaly has been largely positive for the last two years, a fact that seems to have escaped the attention of the climate science community.
From these charts I wish to make 4 key observations:
- Sea ice area expands in winter and contracts in summer giving rise to the cyclical Arctic and Antarctic distributions.
- The Arctic sea ice winter maximum and summer minimum have been declining since records began and in the summer of 2007 the Arctic experienced a sudden increase in summer melt back, a condition that persisted for 5 years until 2013 when things “unexpectedly” reverted to “normal”.
- The decreasing sea ice trend of the Arctic is roughly mirrored by the increasing sea ice trend of the Antarctic.
- The upshot is that the global sea ice anomaly is currently ZERO. The last two years have been more positive than negative and are indistinguishable from records 35 years ago when the records began.
The warmists continue to spread sea ice alarm as if it has continued to disappear at an alarming rate. What is the point in having data if you do not pay attention to what it tells you?
A good example comes from a recent Nature communication*:
Successive cold winters of severely low temperatures in recent years have had critical social and economic impacts on the mid-latitude continents in the Northern Hemisphere. Although these cold winters are thought to be partly driven by dramatic losses of Arctic sea-ice, the mechanism that links sea-ice loss to cold winters remains a subject of debate.
The only response possible to this is “what loss of Arctic sea ice”.
* Weakening of the stratospheric polar vortex by Arctic sea-ice loss. Baek-Min Kim1, Seok-Woo Son, Seung-Ki Min, Jee-Hoon Jeong, Seong-Joong Kim, Xiangdong Zhang, Taehyoun Shim & Jin-Ho Yoon. Nature 2014
In preparing this post, it occurred to me that there must be satellite data on global snow cover. Its a subject I’ve heard very little and know very little about. It seems to get little media attention. For starters, snow cover in the southern hemisphere is of little interest. Its dominated by Antarctica and the absence of other land at high southern latitude makes southern snow cover an insensitive variable. But the northern hemisphere is interesting.
Rutgers University are the curators of the global snow cover data base that begins in November 1966. They have a nice web site from which I managed to download all their data within minutes and a few hours of very pleasurable charting followed. I’ll have a post on this next week, but for starters a couple of summary charts.
Figure 8 Northern hemisphere snow area with a very pronounced annual cycle. Note some missing data at the beginning of the time series. The scale goes to 60 million square miles. There is no obvious trend looking at the data but a regression through the data does reveal a slow decline in snow cover.
In the UK we were told a few years ago that snow would be a thing of the past. That our children would grow up not knowing what snow was. This is hard to reconcile with the great Scottish skiing we’ve had in recent years and the satellite data. A regression through the data does show northern hemisphere snow cover declining slowly. So does that mean that northern hemisphere snow will become a thing of the past?
Figure 9 Plotting only the December data shows that winter snow cover in the northern hemisphere is actually increasing.
Looking just at the data for January we see that the amount of winter snow cover is actually increasing. It is also melting back faster in the spring in a rather complex and interesting picture that I will present in a separate post.
Figure 10 The caption on this IPCC chart says northern hemisphere snow cover while in fact the data are for March and April and are non-represntative.
Here is the IPCC view from 2007. They could have shown the annual picture but that would not have shown what they wanted. Instead they cherry pick data for March and April that does indeed show a decline. The chart of course does not include that vital caveat. And they forget to mention that snow cover from September to February is actually increasing. This is hopeless non-scientific agenda driven cherry picking of data that is designed to deceive. A number of commenters have been asking what motive does the IPCC and body of climate scientists have to deceive governments and the public in this way? I don’t know the answer to that, but some day there will have to be an inquiry into the conduct of this body and their masters at the United Nations.
The view of CO2 from space was the subject of my last post. NASA have just begun their data acquisition with the OCO-2 satellite and it is far to early to say what the data will show. Given that human emissions are tiny compared with the size of the natural flux, I am sceptical that they will be able to detect human emissions at all. It is not obvious that NASA scientists understand this fundamental point and their initial comments about the OCO-2 data are rather discouraging. The excerpt below from the initial results shows below average CO2 over Europe. This did not dissuade NASA from saying this:
Elevated carbon dioxide can also be seen above industrialized Northern Hemisphere regions in China, Europe and North America.
What they ought to have said is that CO2 levels over Europe are below average and not surprisingly human emissions do not show up because they are swamped by the natural background signal.
Finally, I want to leave space to repeat the message from the Vostok ice core that I covered a few weeks ago. At the onset of glaciations, CO2 lags temperature by several thousand years clearly showing that it is NOT implicated in temperature modulation at that time. Petit et al (1999)* in their seminal paper make the observation but then ignore its consequences completely. If the great CO2 lie did not begin with this paper, it certainly was given succour by Petit et al emphasising the co-variance seen between CO2 and temperature at the glacial terminations whilst ignoring the absence of co-variance when Earth is plunged back into glacial conditions.
*  J. R. Petit*, J. Jouzel†, D. Raynaud*, N. I. Barkov‡, J.-M. Barnola*, I. Basile*, M. Bender§, J. Chappellaz*, M. Davisk, G. Delaygue†, M. Delmotte*, V. M. Kotlyakov¶, M. Legrand*, V. Y. Lipenkov‡, C. Lorius*, L. Pe ́ pin*, C. Ritz*, E. Saltzmank & M. Stievenard† (1999) Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. NATURE | VOL 399 | 3 JUNE 1999 |
Figure 1 At glacial terminations, CO2 and temperature are closely aligned because warming triggered by orbital forcing leads to a rise in green house gasses. When the same orbital forcing takes Earth back to glacial conditions CO2 lags by several thousand years (8,000 years on this chart) as indicated by the arrows. Temperature falls dramatically even with elevated CO2. Cold conditions eventually lead to CO2 being pumped down. Temperature controls CO2, not vice versa.
The data from the Vostok ice core shows clearly that temperature controls atmospheric CO2 levels. That is not to say that CO2 has no impact on temperature, but its impact is modest. NASA satellite derived measurements of troposphere temperatures shows a slowly warming trend of about 1.4˚C per century. A significant part of that will be down to natural warming, some of it down to elevated CO2. The satellite data are consistent with a transient climate response less than 1.5˚C. Satellite data on global cloud cover are inversely correlated with surface temperature, no big surprise. The International Satellite Cloud Climatology Project provides unique insight to global climate change, that is mainly natural, but the data are to large extent ignored.
The Global sea ice anomaly is currently zero but has been mainly positive for the last two years. There is no catastrophic loss of sea ice. The northern hemisphere snow cover is largely unchanged since 1967. Winter (September to February) snow cover is increasing while the rate of summer melt (March to August) is also increasing.
Satellite measurements of CO2 by the OCO-2 satellite are in their infancy but cannot be expected to show human emissions against a very large natural background flux. The satellite data should be very helpful in understanding how that natural flux operates.
The IPCC, NASA and the climate science community in general continue to misrepresent all this data for reasons known only to them. It is understandable that the public are confused by what “the scientists” say and why the sceptics refute this. The data is presented in this post and hopefully it speaks for itself.