Some people cite scientists saying there is a “CO2 control knob” for Earth. No doubt there is, but due to the logarithmic effect of CO2, I think of it like a fine tuning knob, not the main station tuner. That said, a new data picture is emerging of an even bigger knob and lever; a nice bright yellow one.
A few months back, I found a website from NOAA that provides an algorithm and downloadable program for spotting regime shifts in time series data. It was designed by Sergei Rodionov of the NOAA Bering Climate and Ecosystem Center for the purpose of detecting shifts in the Pacific Decadal Oscillation.
Regime shifts are defined as rapid reorganizations of ecosystems from one relatively stable state to another. In the marine environment, regimes may last for several decades and shifts often appear to be associated with changes in the climate system. In the North Pacific, climate regimes are typically described using the concept of Pacific Decadal Oscillation. Regime shifts were also found in many other variables as demonstrated in the Data section of this website (select a variable and then click “Recent trends”).
But data is data, and the program doesn’t care if it is ecosystem data, temperature data, population data, or solar data. It just looks for and identifies abrupt changes that stabilize at a new level. For example, a useful application of the program is to look for shifts in weather data, such as that caused by the PDO. Here we can clearly see the great Pacific Climate Shift of 1976/77:
Another useful application is to use it to identify station moves that result in a temperature shift. It might also be applied to proxy data, such as ice core Oxygen 18 isotope data.
But the program was developed around the PDO. What drives the PDO? Many say the sun, though there are other factors too. It follows to reason then the we might be able to look for solar regime shifts in PDO driven temperature data.
Alan of AppInSys found the same application and has done just that, and the results are quite interesting. The correlation is well aligned, and it demonstrates the solar to PDO connection quite well. I’ll let him tell his story of discovery below. – Anthony
Climate Regime Shifts
The notion that climate variations often occur in the form of ‘‘regimes’’ began to become appreciated in the 1990s. This paradigm was inspired in large part by the rapid change of the North Pacific climate around 1977 [e.g., Kerr, 1992] and the identification of other abrupt shifts in association with the Pacific Decadal Oscillation (PDO) [Mantua et al., 1997].” [http://www.beringclimate.noaa.gov/regimes/Regime_shift_algorithm.pdf]
Pacific Regime Shifts
Hare and Mantua, 2000 (“Empirical evidence for North Pacific regime shifts in 1977 and 1989”): “It is now widely accepted that a climatic regime shift transpired in the North Pacific Ocean in the winter of 1976–77. This regime shift has had far reaching consequences for the large marine ecosystems of the North Pacific. Despite the strength and scope of the changes initiated by the shift, it was 10–15 years before it was fully recognized. Subsequent research has suggested that this event was not unique in the historical record but merely the latest in a succession of climatic regime shifts. In this study, we assembled 100 environmental time series, 31 climatic and 69 biological, to determine if there is evidence for common regime signals in the 1965–1997 period of record. Our analysis reproduces previously documented features of the 1977 regime shift, and identifies a further shift in 1989 in some components of the North Pacific ecosystem. The 1989 changes were neither as pervasive as the 1977 changes nor did they signal a simple return to pre-1977 conditions.”
Overland et al “North Pacific regime shifts: Definitions, issues and recent transitions”
[http://www.pmel.noaa.gov/foci/publications/2008/overN667.pdf]: “climate variables for the North Pacific display shifts near 1977, 1989 and 1998.”
The following figure from the above paper show analysis of PDO and Victoria Index using the Rodionov regime detection algorithm. A regime shift is also detected around 1947-48.
The following figure shows regime shift detection for the summer PDO, showing shifts at 1948, 1976 and 1998.
(For detailed information on the 1976/77 climate shift,
Regime Shift Detection in Annual Temperature Anomaly Data
The NOAA Bering Climate web site provides the algorithm for regime shift detection developed by Sergei Rodionov [http://www.beringclimate.noaa.gov/regimes/index.html]. The following analyses use the Excel VBA regime change algorithm version 3.2 from this web site.
The following figure shows the regime analysis of the HadCRUT3 annual global annual average temperature anomaly data from the Met Office Hadley Centre for 1895 to 2009 [http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/annual].
The analysis was run based on the mean using a significance level of 0.1, cut-off length of 10 and Huber weight parameter of 2 using red noise IP4 subsample size 6. Regime changes are identified in 1902, 1914, 1926, 1937, 1946, 1957, 1977, 1987, and 1997. Running the analysis based on the variance rather than the mean results in regime changes in the bold years listed above.
Regime Shift Relationship to Solar Cycle
The NASA Solar Physics web site provides the following figure showing sunspot area.
The following figure compares the Hadley (HadCrut3) monthly global average temperature (from [http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/]) overlaid with the regime change line (red line) shown previously, along with the sunspot area since 1900. The sunspot cycle is approximately 11 years. The sun’s magnetic field reverses with each sunspot cycle and thus after two sunspot cycles the magnetic field has completed a cycle – a Hale Cycle – and is back to where it started. Thus a complete magnetic sunspot cycle is approximately 22 years. The figure marks the onset of odd-numbered cycles with a vertical red line, even-numbered cycles with a green line.
From the figure above it can be seen that the regime changes correspond to the onset of solar cycles and occur when the “butterfly” is at its widest. The most significant warming regime shifts occur at the start of odd-numbered cycles (1937, 1957, 1977, 1997). Each odd-numbered cycle (red lines above) has resulted in a temperature-increase regime shift. Even-numbered cycles (green lines above) have been inconsistent, with some resulting in temperature-decrease regime shifts (1902, 1946) or minor temperature-increase shifts (1926, 1987).
An unusual one is the 1957 – 1966 cycle, which in the monthly data shown above visually looks like a temperature-increase shift in 1957 followed by a temperature-decrease shift in 1964 but the regime detection algorithm did not identify it. This is likely due to the use of annually averaged data in the regime detection algorithm.
The following figure shows the relative polarity of the Sun’s magnetic poles for recent sunspot cycles along with the solar magnetic flux [www.bu.edu/csp/nas/IHY_MagField.ppt]. The regime change periods are highlighted by the red and green boxes. Each one occurs on as the solar cycle is accelerating. The onset of an odd-numbered sunspot cycle (1977-78, 1997-98) results in the relative alignment of the Earth’s and the Sun’s magnetic fields (positive North pole on the Sun) allowing greater penetration of the geomagnetic storms into the Earth’s atmosphere. “Twenty times more solar particles cross the Earth’s leaky magnetic shield when the sun’s magnetic field is aligned with that of the Earth compared to when the two magnetic fields are oppositely directed” [http://www.nasa.gov/mission_pages/themis/news/themis_leaky_shield.html]
The following figure shows the longitudinally averaged solar magnetic field. This “magnetic butterfly diagram” shows that the sunspots are involved with transporting the field in its reversal. The Earth’s temperature regime shifts are indicated with the superimposed boxes – red on odd numbered solar cycles, green on even.
The Earth’s temperature regime shift occurs as the solar magnetic field begins its reversal.
Solar Cycle 24
Solar cycle 24 is in its initial stage after getting off to a late start. An El Nino occurred in the first part of 2010. This may be the start of the next regime shift.