GEOG3839.15, The North American Drought Atlas

1,456 views

Published on

Published in: Education
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,456
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
6
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

GEOG3839.15, The North American Drought Atlas

  1. 1. READING FOR THURSDAYDavid Meko and Connie Woodhouse (2010), Application ofstreamflow reconstruction to water resources management.M.K. Hughes et al. (eds.), Dendroclimatology, Developments inPaleoenvironmental Research.
  2. 2. QUESTIONWhat was Denver Water’s key concernregarding its water supply?
  3. 3. QUESTIONWhat specific test did Denver Water use toassess whether or not tree rings wereskillful estimators of river flow?
  4. 4. h p://www.ldeo.columbia.edu/tree-ring-laboratory/
  5. 5. Ed Cook Lamont-Doherty Earth Observatory
  6. 6. Observed discharge, Colorado River Compact allocation (16.5 MAF)
  7. 7. Low reservoirPhotograph: Glen MacDonald
  8. 8. “ [The early 21st century drought] highlights both the extreme vulnerability of the semi-arid western United States to precipitation deficits and the need to be er understand long-term drought variability ” and its causes in North America. Cook et al., 2004
  9. 9. “ To this end, we have used centuries-long, annually resolved tree-ring records to reconstruct annual changes in both drought and wetness over large ” portions of North America. Cook et al., 2004
  10. 10. THE NORTH AMERICAN DROUGHT ATLAS
  11. 11. Tree-ring chronologies (red dots) Cook et al., JQS, 2010
  12. 12. Palmer Drought Severity Index The PDSI incorporates historical records of precipitation and temperature into a water-balance model to estimate the amount of water available in the soil relative toaverage conditions and is typically produced once a month.
  13. 13. +4 extreme wet -4 extreme drought (compared to ‘average’ for that place)
  14. 14. One hundred years of drought history around Minneapolis-St. PaulSource: North American Drought Atlas
  15. 15. Drought grid (blue dots) Cook et al., JQS, 2010
  16. 16. Network reconstruction
  17. 17. Drought grid (blue dots) Cook et al., JQS, 2010
  18. 18. Source: Woodhouse et al., 2006
  19. 19. Average PDSI, AD 1580 to 1600
  20. 20. HOW DO WE KNOWTHIS WORKS?
  21. 21. empirical comparisons
  22. 22. Dalhart, TX, 1938
  23. 23. Source: David Stahle
  24. 24. Tree ringSource: David Stahle
  25. 25. June 1833 All-time record flooding on the Arkansas, Canadian, and Verdigris Rivers in Oklahoma. 950 displaced Creek and Seminole drown on floodplain farmsteads.Source: David Stahle
  26. 26. Source: David Stahle
  27. 27. Tree-ring records through time Cook et al., Science, 2004
  28. 28. Quality of PDSI estimates from tree rings Cook et al., JQS, 2010
  29. 29. WHY RECONSTRUCT THE PDSI?
  30. 30. Source: David Stahle
  31. 31. Seasonal precipitation ‘bias’ of NADASt. George et al., The Holocene, 2010
  32. 32. APPLICATIONS
  33. 33. Cook et al., 2007, Earth Science Reviews
  34. 34. How has the extent of severedrought changed through time?
  35. 35. Observed (blue) and tree-ring (red) PDSI in ‘The West’
  36. 36. A 1,000 years of drought in the West Cook et al., Science, 2004
  37. 37. How do other aspects of the climate system influence thefrequency or severity of drought?
  38. 38. EL NIÑ0SOUTHERN OSCILLATION
  39. 39. Source: St. George et al., 2010
  40. 40. Can the Drought Atlas help us placehistorical events within a context of long-term environmental change?
  41. 41. Square Tower House Mesa Verde, ColoradoSource: David Stahle
  42. 42. Square Tower House Great Pueblo Drought Mesa Verde, Colorado A.E. Douglass (1929)Source: David Stahle
  43. 43. North American Drought Atlas h p://www.ncdc.noaa.gov/cgi-bin/paleo/pd08plot.pl
  44. 44. Source: Ingmar Zahorsky
  45. 45. “ Much of the world’s population lives in monsoon Asia and depends on monsoon rainfall for water ” and agricultural fertility. Wahl and Morrill, 2010
  46. 46. Average spatial pa erns of precipitation and wind during summerE R Wahl, C Morrill Science 2010;328:437-438
  47. 47. MONSOON ASIA DROUGHT ATLASh p://www.ncdc.noaa.gov/paleo/pubs/cook2010/cook2010.html
  48. 48. Photograph: Kevin Anchukaitis
  49. 49. Tree-ring records across Monsoon AsiaE R Cook et al. Science 2010;328:486-489
  50. 50. Tree rings show extent of ‘Great Drought’, 1876-1878E R Cook et al. Science 2010;328:486-489
  51. 51. Was the ‘Great Drought’ caused by ENSO or the North Pacific Ocean?E R Cook et al. Science 2010;328:486-489
  52. 52. “ The MADA is a crucial step forward for paleoclimate studies in a region that is of great social and climatological interest, but where the development of tree-ring archives faces immense challenges and ” instrumental data coverage is limited. Wahl and Morrill, 2010
  53. 53. READINGEugene Wahl and Carrie Morrill (2010), Towardunderstanding and predicting monsoon pa erns.Science 328, 437-438.
  54. 54. GRADUATE STUDENT READINGBüntgen et al. (2011), 2500 years of European climatevariability and human susceptibility. Science 331, 578-582.

×