Spring 2008: Patterns and mechanisms of decadal climate variability
last updated May 15, 2008 (check back frequently and reload cached pages for updates)
Registration information
Background reading

Click for options and more information

<1976-2000> - <1951-1975> NCEP-NCAR Reanalysis surface T (colors),
pressure (contours), winds (vectors); click on  figure for data sources

Driven by the potential for predictability, the overlap of timescales between anthropogenic forcing and interannual variability, and the emergence of historal data analyses, semiquantitative high resolution paleoclimatology, and coupled climate model simulations, a number of mechanisms to explain decadal climate variability have been proposed in recent years.  We will explore the viability of these hypotheses within a context framed by modern physical climatology.

To appeal to a broad cross-section of graduate students across departments such as ATMO, GEOS, GEOG, LTRR, HWR, Arid Lands and EEB, class sessions will be divided among instructor-led lectures on relevant fundamentals of physical climatology, and student-led parsing of classic and current literature.  Although students are encouraged to register (so the course can go!), auditing and sitting in is highly encouraged for any or all of the semester.  I only ask your active engagement in the sessions you attend.

This course is a work-in-progress, and its basis is a long-overdue paper on the subject I owe to Reviews of Geophysics.  Check back as the semester approaches for more details on readings and subject matter.


By the conclusion of the semester, students should have developed their own opinions on the following topics:

  1. What are the robustly observed spatial, temporal and spectral features of decadal climate variability?
  2. What are current hypotheses on the mechanisms controlling forced and unforced decadal variability in the climate system? Are these mechanisms consistent with the observations (modern, historical, proxy paleoclimatic), or are new mechanisms required?
  3. Are observed and hypothesized patterns of decadal climate variability periodic and/or predictable?
And students will have practiced the following skills:
  1. Interpretation of multivariate spatiotemporal analyses and uncertainties routinely presented to describe decadal variations in climate data, climate proxy data, and general circulation modeling results. 
  2. Formulation, presentation and defense of a scientific argument, as well as one's own opinion on the matter.



Instructor: Michael Evans , Laboratory of Tree-Ring Research, 214 W. Stadium.  ph 626-2897;  email:  Office hours: Friday, 1-2:15pm, W. Stadium 214, or by appointment.  Please email with questions or for more information.  I will try to answer emails within 24 hours.

Location and Time: Gould-Simpson Bldg., Rm. 209, Monday and Wednesday, 1:00-2:15pm (subject to negotiation with course participants).  Please contact me if this is scheduling creates a conflict for you, as we may be able to adjust it.

Registration info  

This course is cross-listed between Atmospheric Sciences (home department) and Geosciences.  We are section 002.  See the catalog listing for details.  


Prerequisite:  An interest in the nature and mechanisms of decadal climate variability from a range of perspectives, including modern, historical, and paleo observations, and climate modeling.  Prior or current coursework in oceanography, meteorology and climatology will be helpful, but we will begin with fundamentals, especially in lecture sessions.

Additional reading and course materials: Per copyright fair use guidelines, I will  provide them electronically as password protected PDF files, served from this webpage.


Background reading

Further background on the mechanisms and patterns of climate variability is available from the following excellent sources, some of which I have available for loan:


Syllabus (subject to revision)
Discussion Leader
January 16 General introduction (3.4Mb pdf); Logistics Mike Evans (MNE)
Course questionnaire
January 23 (21 = MLK Day)
An introduction to modern and historical climate data and analysis (3.4 Mb pdf).  Overhead shown in class is here.
  1. Rayner et al. (2003) [8.6Mb pdf]
  2. Schubert et al. (2004) [1.4Mb pdf]
Reading focus questions and session summary are here.
January 28/30
An introduction to proxy paleoclimate data and analysis (2.1 Mb pdf); multiproxy climate field reconstructions (3.4 Mb pdf)
Toby A.
  1. NRC (2006) Ch. 4-9, 11 [3.6Mb pdf]
  2. Mann et al. (2000)
Reading focus questions and session summary by Adam C. are here.
Data exercise 1 is here.
February 4/6
Null hypothesis:

The climate has "memory" (1.5 Mb pdf); Continuum climate variability (3 Mb pdf)
Bill S.
  1. Pierce (2001), section 2 [443Kb pdf]
  2. Huybers and Curry (2006) [465Kb pdf]
Reading focus questions and session summary by Nick M. are here.
February  11/13
Pacific sector: Observations:

The signature of ENSO in the  tropical Pacific and global climate (2.5 Mb pdf); ENSO-like interdecadal variability (1.5 Mb pdf)
Alys T.
  1. Garreaud and Battisti (1999) [373Kb pdf]
Reading focus questions and session summary by Tyson S. are here.
Data exercise 2 is here; to be discussed 2/18 in class.
February 18/20 Pacific sector: Mechanisms:

Introduction to climate modeling (8.9 Mb pdf); Models for Pacific decadal variability (5.0 Mb pdf)
Adam C./Toby A.
  1. Newman et al. (2003)  [268 Kb pdf]
  2. Latif (1998) [736 Kb pdf]
Reading focus questions and session summary by Nick M. are here.
February 25/27
Pacific sector: Predictability:

Review of Rossby wave mechanics (1.5 Mb pdf); Is the PDO predictable? (1 Mb pdf; additional notes on linear inverse modeling are here.)
Shey S.
  1. Newman (2007) [3.3 Mb pdf]
Reading focus questions and session summary by Alys T. are here.
March 3/5
Indian sector: Observations:

Indian Ocean climatology, introduction to coral paleoclimatology (2.4 Mb pdf); The IOD from modern and paleo observations (1.6 Mb pdf)
Shey S.
  1. Saji et al. (1999) [388 Kb pdf]
  2. Charles et al. (2003) [1.2 Mb pdf]
Reading focus questions and session summary by Ali M. are here.

Data Exercise 3 is here.
March 10/12
Indian sector: Mechanisms/Predictability:

Kelvin waves and Ekman divergence (1.2 Mb pdf); Is the IOD predictable?  (12 Mb pdf)
Tyson S.
  1. Webster et al. (1999) [984 Kb pdf]
  2. Luo et al. (1997) [3.6 Mb pdf]
Reading focus questions and session summary by Adam C. are here.
March 17/19
No class (Spring Break)
March 24/26 Atlantic sector: Observations

Atmospheric climatology of the North Atlantic Basin and introduction to varved marine sediment records of surface ocean conditions (853Kb pdf); Is there decadal variability in the North Atlantic? (9 Mb pdf)
Alys T./Nick M.
  1. Hurrell (1995) [1.5 Mb pdf]
  2. Black et al. (1999) [444 Kb pdf]
  3. Thompson and Wallace (2001) [632 Kb pdf]
Reading focus questions and session summary by Bill S. are here.
March 31/April 2
No class: Mike in Tahiti

April 7/9
Atlantic sector: Mechanisms

Basics of the  thermohaline circulation (1 Mb pdf); An ocean-atmosphere mechanism for interdecadal THC variations (3.4 Mb pdf)
Bill S.
  1. Dong and Sutton (2005) [3.2 Mb pdf]
Reading focus questions and session summary by Toby A. are here.
April 14/16
Atlantic sector: Predictability:

Introduction to regression mapping using Ingrid and the IRI Data Catalog (pdf); Is the NAO/NAM predictable? (1.2 Mb pdf)

Data Exercise 4 is here.
Tyson S.
  1. Rodwell et al. (1999) [575Kb pdf]
Reading focus questions and session summary by Shey S. are here.
April 21/23
Antarctic sector: Observations:

Data Exercise 4 review; Reanalysis Redux (1.9 Mb pdf); Is there decadal variability in the SAM?  (11 Mb pdf)

Adam C.
  1. Thompson and Wallace (2000) [561Kb pdf]
  2. Jones and Widmann (2004)  [196Kb pdf]; supplementary docs are here and here.
Reading focus questions and session summary by Tyson S. are here.
April 28/30 Antarctic sector: Mechanisms/Predictability
Very brief overview of southern ocean sector climate and oceanography (448Kb pdf); a mechanism for low frequency variation in the southern annular mode (4 Mb pdf)
Nick M.
  1. Hall and Visbeck (2002) [2.2 Mb pdf]
Reading focus questions and session summary by Bill S. are here.
May 5/7
A strawman framework for decadal climate variability? (1.3Mb pdf);  Wrap up MNE/Class
  1. Quadrelli and Wallace (2004) [2 Mb pdf]
Reading focus questions and session/course summary by the class are here.