RSS (Remote Sensing Systems of Santa Rosa, CA) RSS Microwave Sounder Unit (MSU) lower troposphere global temperature anomaly data for July 2008 was published today and has moved a bit above the zero anomaly line, with a value of 0.147°C for a positive change (∆T) of 0.112°C globally from June 2008.
RSS
2008 1 -0.070
2008 2 -0.002
2008 3 0.079
2008 4 0.080
2008 5 -0.083
2008 6 0.035
2008 7 0.147
I rather expected it to go up a bit, given that La Nina has diminsihed, plus the NH has a greater landmass than the SH, and we are in summer. But compared though to July 2007, at 0.363, it is still lower, down 0.216.
Click for larger image
PG,
Any evidence besides that graph? That is a lot of ice to melt when there is already fall in the air where I live, 45° N, and days are getting shorter. I am just asking because your cryptic comment seems to imply something is going on. I guess I will check CA.
Pierre:”I’m just the messenger,
Arctic sea ice could reach 2007 levels by next week.
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png”
The link’s graph contains the magical “1979-2000 average”. I still ask the question, Why are the years 2001-2007 not included in this average? My bet is that it will lower the average and the lines for 2007 & 2008 will appear more normal. Well, we certainly can’t have that!
jeez (01:59:47) :
Paul, ignore my email, for a second I thought I had deleted one of your posts.
No problem Charles. I’ve not looked at my emails for a few days, but I will ignore.
A little off topic. I appears we have had hailstone here in the UK. A little unusual for summer! Must be very cold up there.
http://news.bbc.co.uk/1/hi/in_pictures/7546933.stm
[…] wattsupwiththat.wordpress.com Tags: global temperatures, temperature, temperature data, temperatures Related Posts […]
Since a negative PDO is mainly a signal for a La Nina-esque ENSO pattern, I’m mainly interested in the Pacific. If the worm has really turned we should be seeing either:
a)ENSO neutral evolving into a weak/short term El Nino for 2009.
b)ENSO neutral continuing through the winter and maybe spring of 2009
c)ENSO neutral evolving into another La Nina by summer of 2009.
if ENSO transitions from neutral to a moderate El Nino or stronger, then it is back to the drawing boards.
dreamin, I assume you know that almost all of ‘climate science’, the IPCC and AGW theory is dependent on persistence of forcings, or in your terms ‘climate memory’.
No, I didn’t know that. Or at least I hadn’t given it much thought. But now that you mention it, it makes sense.
If forcings (things that make the climate warmer or cooler) aren’t persistent, then we can toss all climate science to date in the bin.
Personally, I’m sceptical of the forcings persistence model.
I’m skeptical too, and anyway, one should consider the possibility that any “forcings” themselves are transient and the result of noise. Let me give you an example:
If you are playing blackjack in a casino, your odds of winning in a particular hand are not independent of your odds of winning the previous hand. Because situations can arise where the remaining cards are very rich in tens and face cards. In those situations, you have a better chance of having a winning streak than would be predicted by a model which assumed that each hand was independent.
By analogy, it seems possible that temperatures could engage in a bona fide warming trend (i.e. a trend which passes statistical tests) but which doesn’t have any deep meaning. Perhaps if some ocean current shifts from one state to another.
Thus, if a butterfly in China can cause a rain storm in New York, we should consider the possibility that the same butterfly can cause an ice age.
Anyway, if external forcings drive the climate, then what caused the Little Ice Age? What caused the Medieval Warm Period? And why can scientists not predict global temperature anomalies over a 5 or 10 year time period?
Seems to me the response of many climate scientists is that (1) the little ice age didn’t happen; (2) the medieval warm period didn’t happen; and (3) short term noise makes it impossible predict over a 5 or 10 year period, but it’s possible over a 25 or 50 year period.
(1) and (2) strike me as false. (3) strikes me as an unsupported, ad hoc explanation which conveniently delays falsification for another 20 years or so. i.e. it has all the red flags of BS.
One reason being what you point out, global temperatures look too random on shorter timescales. The standard explanation is weather noise, but I see no reason why the Earth’s weather in aggregate (ie its climate) should be noisy, as weather is just transfer of heat and moisture from one place to another.
I basically agree with you. It seems to me that under the external forcings view, the total heat in the system should be monotonically increasing.
Simply eyeballing the temperature vs year graphs indicates a “cycling”. And, by the look of it, we’ve been near a “local minimum” — so an upturn just about now is not unexpected. On the other hand, continuing a downward trend would be very-very interesting.
I am interested to see how high we will get during this next multi-year “up cycle”. That is, are temperatures cycling down, up, or level.
Its also interesting to see how well IPCC contributors’ climate model predictions are tracking with actual multi-year temperature cycles (they are not even close, in my opinion).
Leon …
You mention the trends. I personally have a big problem with the way people handle trends in Climate. As pointed out, Climate is noisy. Depending on where you decide to start your trend line determines what kind of trend you get. Even with this recent cooling, the weight of the warmer temps associated with the top of the curve (ie., 1995-2006) of the latest warm blip is over represented in the trend analysis, thus guaranteeing that the overall trend will be positive. It would make more sense to me if they started the trend line at the last temperature peak (1930-somethin’), that way the lower temps of the last cooling get figured in as well.
I recall that Anthony featured a post here where someone (or maybe he himself) did an analysis of small trends within the longer term temperature record since 1979. IMO, this is a much more accurate way of looking at it. If not, then it’d be better to look at the trend over multicentury spans.
As many folks have noted …. there’s just too much cherry picking going on in Climate Science.
Off topic but interesting for all chartists:
http://sl.farmonline.com.au/news/nationalrural/agribusiness-and-general/general/sunspots-linked-to-soi/1237781.aspx
old construction worker,
Latest news is that Hansen wants to set up one of them Stevenson screens over that 800°F hot-spot in California. Can’t get better siting than that!
Mike Bryant,
Dr Baker appears to be re-hashing Lanscheidt’s science.
Not much new there, really.
Anyway, if external forcings drive the climate, then what caused the Little Ice Age? What caused the Medieval Warm Period?
External forcings does not mean extra-terrestrial. There are many terrestrial events that have wide-reaching impacts on the climate. Since you are legitimately asking, let me give you the textbook, accepted idea which is used to explain the LIA. Note that the MWP is not really considered to be a period of global warmth; its effects were most profound in the North Atlantic, and there is not definitive evidence that it occurred to the same extent globally.
The LIA was caused by several things, but two important ones stick out. First, the LIA was a period of anomalously high amounts of volcanic activity. The eruption of volcanoes has two effects: on the long-term, they increase the temperature of the climate because the black carbon aerosols and GHG’s they spout contribute a warming effect. However, in the short-term, they can dramatically cool the climate (as evidenced by the Pinatubo eruption in the early 90’s). The period of high volcanic activity led to a large amount of aerosols being deposited in the stratosphere; they shielded a great deal of incoming radiation.
To add to the decrease of incoming radiation, the sun also underwent the “Maunder Minimum.” Although there really isn’t a physical mechanism which has connected sunspots to a cooling sun, it is a highly popular hypothesis, and the LIA and especially its peak minimum highly correlate to the maunder minimum.
Finally, it has been hypothesized that the oceanic thermohaline circulation may have abruptly shifted, altering the Gulf Stream which helps high-latitude portions of Europe in a warmer trend.
These are the big ideas which go into the LIA. They’re considered “external forcings” because they’re not part of the atmosphere.
Hmmm, where I work is near a well-documented weather station (LAX) and the posted numbers for July were two degree F below the normal. August so far is even.
Simply eyeballing the temperature vs year graphs indicates a “cycling”. And, by the look of it, we’ve been near a “local minimum” — so an upturn just about now is not unexpected.
I disagree. Take a look at a stock market graph over a time period of about a year. It’s easy to think that there are predictable cycles, but there are not.
For better or for worse, a lot of my thinking about climate models is informed by knowledge of financial markets and how they work.
For better or for worse, a lot of my thinking about climate models is informed by knowledge of financial markets and how they work.
No offense, but that’s definitely “for worse.” Climate models operate on physical principles which can be summarized into mathematical equations and approximations. Predictive financial models do not.
While the stock market and the atmosphere are similar in that they are examples of chaotic systems, they are chaotic for different reasons. The financial market is chaotic because there is no hard-wired physical basis for the phenomena it exhibits. On the other hand, the atmosphere is chaotic because we do not have a full understanding of it and its influences – however, we do have enough of an understanding to begin analyzing it.
Walter,
Thanks for the link. I slapped the data into a spreadsheet locally so I could play with it. I must be missing something though because the data says that Aug 5th 2008 was -.12 F lower than Aug 5th, 2007 in the comment section, but when I look at Aug 5 2007 the reading was 272.649 and Aug 5, 2008 is 272.583, which, even with my somewhat limited arithmetic skills (aided immensely by Excel) is -.066, not -.12. I wonder if I’m misreading the data somehow?
Walter,
This is the data I was referring to above. Sorry for not including it.
http://discover.itsc.uah.edu/amsutemps/data/amsu_daily_85N85S_chLT.r001.txt
JP: If we turn the common understanding about the PDO and ENSO around… If the frequency of La Nina episodes outnumber El Ninos, the PDO will remain negative. Will La Ninas be more frequent than El Ninos for the next 20 to 30 years? Your guess is as good as mine. Looks like they’re trying.
Paul (and others),
Thanks for those graphs. One thing that stands out (particularly in the 12 month moving average plots) is that there seems to be a ~4 year cycle in global temps. It’s not really noisy on a month to month scale, it’s a steady rollercoaster of ups and downs, not a washboard gravel road, so to speak. That is, there are dips in ~’85, ’89, 93, ’96, ’00, ’04, and ’08. The global temp picks a vector and heads that way for about 2 years, then there’s a fairly rapid reversal from these nadirs to peaks a couple years later.
I have no idea or have never read any reason for such a short cycling. I could undersand a yearly cycle, or an 11ish year cycle, but the only 4-year cycle that matches this data set well is our presidential elections…hmmm
Matt
Paul Shanahan- “A little off topic. I appears we have had hailstone here in the UK. A little unusual for summer! Must be very cold up there.”
Hailstones are quite common in summer months and have nothing to do with cool ground temperatures. In the UK,especially the southern half this time of year always has three days of fine weather folloed by a thundery outbreak. Hailstorms are very common during thunderstorms.
Back to the July temperature anomoly, we now have a neutral ENSO and ‘coolphase’ PDO. The solar minimum is well established (one sunspot last month) so why is the temperature still above average? As I understand the theory, low sunspot activity allows more cosmic rays to enter the earths atmosphere forming more clouds by increased ion-induced aerosol nucleation, hence a cooling. As this is a direct process there should be no temperature lag.
Temperatures should be falling, but they are not, could there be another reason?
dreamin –
Having tried stock trading (and all the study and modeling that goes with it), I agree with your stock market observation. I think the fact that humans are so involved has a lot to do with that.
Regarding the “global temperature”. I think “cycling” of various natural phenomena have been and will be found to impart a cyclic effect on global temperature — the result is a complex cycling of global temperature over various time scales which may look random at times.
Why? Global temperature is driven by natural forces not subject to easy modification by humans (even AGW). Some are very cyclic (e.g. planetary motions). I think few are truly random in effect (with the major exceptions of random volcanic activity and comet strikes occasionally causing major world wide temperature events). I think that most (not all) of the variability is ultimately understandable after the fact. On the other hand, future global temperature may never be completely predictable because some needed data may never be available in advance.
Just my opinions. A relative newcomer, I continue to study global temperature phenomena and don’t know what I am talking about.
dreamin, et al.,
The question about persistence is an interesting one. The Hurst exponent is one way to look at, or try to measure, persistence or memory in data. So I just took a look at calculating Hurst exponents for a variety of UAH temperature series. I’ll just post the results, in an order that makes some sense to me, and invite comment. All this is based on UAH, monthly, 1978:12 through 2008:06.
Globe: 0.9057
That’s a fairly high degree of persistence (the range is .5 to 1, with randomness at the low end, and autocorrelation at the upper end).
But it varies quite a bit latitudinally:
Northern Polar: 0.904806
Northern Extra Tropics: 0.967697
Tropics: 0.732871
Southern Extra Tropics: 0.862738
Southern Polar: 0.689742
Breaking out the Northern Extra Tropics between ocean and land:
Ocean: 0.986821
Land: 0.918612
And the Tropics:
Ocean: 0.721679
Land: 0.752451
Comments, anyone?
Basil
Sunspot cycles linked to SOI??
http://sl.farmonline.com.au/news/nationalrural/agribusiness-and-general/general/sunspots-linked-to-soi/1237781.aspx
Mike Keep
it will propably take a number of colder years to cool down ocean temperatures and roll backthe arctic ice anomaly that are forcing against a very juvenescent cooling trend. The Maunder Minimum also did not happen in the first year after the end of the medieval warm period.