The seasonality of moisture-sensitive tree-ring records

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Scott St. George

Presentation given at PAGES 2K meeting in Tucson, Arizona, October 28, 2011.

Bildung Technologie

THE

SEASONALITY
OF MOISTURE-SENSITIVE TREE-RING RECORDS

MY DISSERTATION PROPOSAL
“...this project will establish a new network of moisture-
sensitive tree-ring sites within the WRB that will allow
researchers to estimate hydroclimatic conditions in the
basin during the past 200 – 500 years.”

X
MY DISSERTATION PROPOSAL
“...this project will establish a new network of moisture-
sensitive tree-ring sites within the WRB that will allow
researchers to estimate hydroclimatic conditions in the
basin during the past 200 – 500 years.”

100%
MORE CERTAIN
80%

60%

explained
variance
40%

20%

LESS CERTAIN
0%

Canada USA

100%
MORE CERTAIN
Woodhouse et al., 2006
Meko et al., 2001
80% Sacramento River
Upper Colorado River

Meko et al., 2007
Colorado River
Woodhouse, 2007
Middle Boulder Creek

60%

explained
variance
40%

20%

LESS CERTAIN
0%

Canada USA

QUESTION
What is the seasonality of moisture-sensitive
tree-ring records across North America?

QUESTION drought
What is the seasonality of moisture-sensitive
tree-ring records across North America?

NORTH AMERICAN
DROUGHT ATLAS
h p://www.ncdc.noaa.gov/paleo/pdsi.html

Source: Cook et al., Earth Science Reviews, 2007

INSTRUMENTAL
PDSI
WINTER SUMMER
total precipitation total precipitation

INSTRUMENTAL TREE-RING
PDSI PDSI
WINTER SUMMER WINTER SUMMER
total precipitation total precipitation total precipitation total precipitation

Point-to-point correlations, Summer Precipitation & Summer PDSI (Instrumental)
St. George et al., The Holocene, 2011

0.0 0.2 0.4 0.6

Point-to-point correlations, Summer Precipitation & Summer PDSI
St. George et al., The Holocene, 2010

0.0 0.2 0.4 0.6

Point-to-point correlations, Winter Precipitation & Summer PDSI
St. George et al., The Holocene, 2010

Seasonal precipitation ‘bias’ of NADA

St. George et al., The Holocene, 2010

WINTER-SENSITIVE SUMMER-SENSITIVE
RECORDS RECORDS

WINTER-SENSITIVE SUMMER-SENSITIVE
RECORDS RECORDS
HIGH spatial coherence

STRONG connections to
remote forcings

GOOD hydrological proxy

WINTER-SENSITIVE SUMMER-SENSITIVE
RECORDS RECORDS
HIGH spatial coherence LOW spatial coherence

STRONG connections to MODEST connections to
remote forcings remote forcings

GOOD hydrological proxy POOR hydrological proxy

ENSO (the Cold Tongue Index) correlated against reconstructed summer PDSI
St. George et al., The Holocene, 2010

GENERAL
TENDENCY
WITH

MORE AND MORE
EXCEPTIONS

1747
The International Tree-Ring Databank houses

ring-width chronologies
from North America

QUESTION
Are our analytical methods appropriate
when we apply them to very large datasets?

“ This method of selecting proxies by screening a potentially
large number of candidates for positive correlations runs
the danger of choosing a proxy by chance.

Gerd Bürger
”
Science 2007

1747
RING-WIDTH
0.95
SIGNIFICANCE
CHRONOLOGIES LEVEL

1747
RING-WIDTH
0.95 ➔
SIGNIFICANCE
87
CHRONOLOGIES
CHRONOLOGIES LEVEL THAT CORRELATE
WITH JUST ABOUT
ANYTHING

1
We should test our models against noise.

Decadal ‘hotspots’ in winter precipitation

0% 10% 20% 30% variance
Ault and St. George, Journal of Climate, 2010

tree-ring width records
International Tree-Ring Databank

St. George and Ault, JGR-A, 2011

decadal target

decadal ‘noise’

St. George and Ault, JGR-A, 2011

QUESTION the entire set of
What is the seasonality of moisture-sensitive
tree-ring records across North America?

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The recently published educational policy document under the title ‘National Education Policy Reform’ (NEPF for short) has been the subject of much criticism. Various parties have expressed their grave concerns about this proposed NEPF on many platforms. This document attempts to cover some angles which the author deems less covered in other criticisms. This critique is by no means complete or exhaustive; rather, the author prefers that it be read in conjunction with other such criticisms.

A Critique of the Proposed National Education Policy Reform

Chameera Dedduwage

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Discover the Kisan Call Centre: Your Gateway to Agricultural Assistance KISAN CALL CENTRE In order to harness the potential of ICT in Agriculture, Ministry of Agriculture & Farmers Welfare launched the scheme “Kisan Call Centres” (KCCs) on January 21, 2004. Main aim of the scheme is to answer farmers’ queries on a telephone call in their own language. These call centres are working in 21 different locations in the country covering all the States and UTs. A countrywide common eleven digit Toll Free Number 1800-180-1551 has been allotted for Kisan Call Centre. This number is accessible through mobile phones and landlines of all telecom networks including private service providers. Replies to the farmers’ queries are given in 22 local languages. Kisan Call Centre services are available from 6.00 AM to 10.00 PM on all seven days of the week at each KCC location. Kisan Call Centre agents known as Farm Tele Advisors (FTAs), who are graduate or above (i.e. PG or Doctorate) in Agriculture or allied sectors (Horticulture, Animal Husbandry, Fisheries, Poultry, Bee-Keeping, Sericulture, Aquaculture, Agricultural Engineering, Agricultural Marketing, Bio-Technology, Home Science, etc.) and possess excellent communication skills in respective local language. Queries which cannot be answered by FTAs are transferred to higher level experts. These experts are Subject Matter Specialists (SMSs) of State Departments of Agriculture (SDAs), ICAR Institutes, KVKs and State Agricultural Universities (SAUs). A Kisan Knowledge Management System (KKMS) has been developed to capture all the details of the caller and sending gist of answer given through SMS. KKMS has its independent website : http://dackkms.gov.in. The KCC, FTAs working at various KCC locations throughout the country have access to this website through their specific IDs and password provided to them. Welcome to the Kisan Call Centre - your one-stop destination for agricultural assistance and support. With dedicated team of experts and cutting-edge technology, we're here to revolutionize the way farmers access information and guidance. In this powerpoint, we delve into the world of the Kisan Call Centre, exploring how it functions, the services it offers, and the impact it has on farmers across the nation. From real-time advisory services to multilingual support, we'll uncover the key features that make the Kisan Call Centre an indispensable resource for farmers of all backgrounds. Join us as we showcase the achievements of the Kisan Call Centre, from its enhanced farmer outreach to its empowerment of women farmers. Discover how our feedback mechanism ensures continuous improvement, and learn about our collaborations with agricultural institutions to provide accurate and reliable information. Whether you're a seasoned farmer or just starting out, the Kisan Call Centre is here to support you every step of the way. Subscribe now to stay updated on the latest agricultural insights

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The seasonality of moisture-sensitive tree-ring records

1. THE SEASONALITY OF MOISTURE-SENSITIVE TREE-RING RECORDS

3. MY DISSERTATION PROPOSAL “...this project will establish a new network of moisture- sensitive tree-ring sites within the WRB that will allow researchers to estimate hydroclimatic conditions in the basin during the past 200 – 500 years.”

4. X MY DISSERTATION PROPOSAL “...this project will establish a new network of moisture- sensitive tree-ring sites within the WRB that will allow researchers to estimate hydroclimatic conditions in the basin during the past 200 – 500 years.”

5. 100% MORE CERTAIN 80% 60% explained variance 40% 20% LESS CERTAIN 0% Canada USA

6. 100% MORE CERTAIN Woodhouse et al., 2006 Meko et al., 2001 80% Sacramento River Upper Colorado River Meko et al., 2007 Colorado River Woodhouse, 2007 Middle Boulder Creek 60% explained variance 40% 20% LESS CERTAIN 0% Canada USA

7. 100% MORE CERTAIN Woodhouse et al., 2006 Meko et al., 2001 80% Sacramento River Upper Colorado River Meko et al., 2007 Colorado River Woodhouse, 2007 Middle Boulder Creek 60% Case and MacDonald, 2003 Saskatchewan River explained Beriault and Sauchyn, 2006 Churchill River Bonin and Burn, 2005 variance Athabasca River 40% Watson and Luckman, 2005 Gedalof et al., 2007 Bow River Columbia River 20% LESS CERTAIN 0% Canada USA

8. SEASONALITY

9. QUESTION What is the seasonality of moisture-sensitive tree-ring records across North America?

10. Source: David Stahle

11. QUESTION drought What is the seasonality of moisture-sensitive tree-ring records across North America?

12. NORTH AMERICAN DROUGHT ATLAS h p://www.ncdc.noaa.gov/paleo/pdsi.html

13. Source: Cook et al., Earth Science Reviews, 2007

14. INSTRUMENTAL PDSI WINTER SUMMER total precipitation total precipitation

15. INSTRUMENTAL TREE-RING PDSI PDSI WINTER SUMMER WINTER SUMMER total precipitation total precipitation total precipitation total precipitation

16. Point-to-point correlations, Summer Precipitation & Summer PDSI (Instrumental) St. George et al., The Holocene, 2011

17. 0.0 0.2 0.4 0.6 Point-to-point correlations, Summer Precipitation & Summer PDSI St. George et al., The Holocene, 2010

18. 0.0 0.2 0.4 0.6 Point-to-point correlations, Winter Precipitation & Summer PDSI St. George et al., The Holocene, 2010

19. Seasonal precipitation ‘bias’ of NADA St. George et al., The Holocene, 2010

20.

21. WINTER-SENSITIVE SUMMER-SENSITIVE RECORDS RECORDS

22. WINTER-SENSITIVE SUMMER-SENSITIVE RECORDS RECORDS HIGH spatial coherence STRONG connections to remote forcings GOOD hydrological proxy

23. WINTER-SENSITIVE SUMMER-SENSITIVE RECORDS RECORDS HIGH spatial coherence LOW spatial coherence STRONG connections to MODEST connections to remote forcings remote forcings GOOD hydrological proxy POOR hydrological proxy

24. EL NIÑ0 SOUTHERN OSCILLATION

25. ENSO (the Cold Tongue Index) correlated against reconstructed summer PDSI St. George et al., The Holocene, 2010

26. QUESTION drought What is the seasonality of moisture-sensitive tree-ring records across North America?

27. Seasonal precipitation ‘bias’ of NADA St. George et al., The Holocene, 2010

28. GENERAL TENDENCY WITH MORE AND MORE EXCEPTIONS

29. QUESTION What is the seasonality of moisture-sensitive tree-ring records across North America?

30. Source: David Stahle

31. 1747 The International Tree-Ring Databank houses ring-width chronologies from North America

32. QUESTION Are our analytical methods appropriate when we apply them to very large datasets?

33. COMMON ‘OPTIMAL’ PATTERNS PREDICTORS

34. Bürger, Science, 2007

35. “ This method of selecting proxies by screening a potentially large number of candidates for positive correlations runs the danger of choosing a proxy by chance. Gerd Bürger ” Science 2007

36. Carlo Emilio Bonferroni 1892 - 1960

37. Source: David Stahle

38. 1747 RING-WIDTH CHRONOLOGIES

39. 1747 RING-WIDTH 0.95 SIGNIFICANCE CHRONOLOGIES LEVEL

40. 1747 RING-WIDTH 0.95 ➔ SIGNIFICANCE 87 CHRONOLOGIES CHRONOLOGIES LEVEL THAT CORRELATE WITH JUST ABOUT ANYTHING

41. 2 approaches that might help

42. 1 We should test our models against noise.

43. Decadal ‘hotspots’ in winter precipitation 0% 10% 20% 30% variance Ault and St. George, Journal of Climate, 2010

44.

45. tree-ring width records International Tree-Ring Databank St. George and Ault, JGR-A, 2011

46. Carlo Emilio Bonferroni 1892 - 1960

47. Source: Michael Koukoullis