development of bias-corrected precipitation database and climatology for the arctic regions

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Development of Bias- Corrected Precipitation Database and Climatology for the Arctic Regions Daqing Yang, Principal Investigator Douglas L. Kane, Co-Investigator Institute of Northern Engineering University of Alaska Fairbanks David R. Legates, Co-Investigator Center for Climatic Research Department of Geography University of Delaware

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Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions. Daqing Yang, Principal Investigator Douglas L. Kane, Co-Investigator Institute of Northern Engineering University of Alaska Fairbanks David R. Legates, Co-Investigator Center for Climatic Research - PowerPoint PPT Presentation

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Page 1: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Development of Bias-Corrected Precipitation Database and

Climatology for the Arctic Regions

Daqing Yang, Principal Investigator

Douglas L. Kane, Co-Investigator

Institute of Northern Engineering University of Alaska Fairbanks

David R. Legates, Co-Investigator

Center for Climatic Research

Department of Geography University of Delaware

Page 2: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Outline

• Background /Goals

• Methods

- Results and applications of WMO gauge intercomparison project

• Data Sources

• Major Tasks

• Results/Products/Impacts

Page 3: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Uncertainties of Precipitation Records and Climatology in the Arctic regions

• Sparseness of the precipitation observation networks;

• Uneven distribution of measurement sites, i.e. biased toward coastal and the low-elevation areas;

• Spatial and temporal discontinuities of precipitation measurements induced by changes in observation methods and by different observation techniques used across national borders; and

• Biases of gauge measurements, such as wind-induced undercatch, wetting and evaporation losses, and underestimate of trace amount of precipitation.

Page 4: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Research Goals

• Evaluate and define the accuracy of precipitation measurements in the Arctic regions.

• Implement the consistent bias-correction methods over the pan-Arctic, i.e. Alaska, northern Canada, Siberia, northern Europe, Greenland, and the Arctic Ocean.

• Develop biased-corrected and compatible precipitation database (including grid products) and climatology for the Arctic regions as a whole.

Page 5: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

US Wyoming snow system in Barrow, AK WMO double fence intercomparison reference (DFIR)

in Barrow, AK

Page 6: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

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Wind speed at gauge height (m/s)

Rat

io o

f gau

ge c

atch

to th

e D

FIR

(%

)Canadian Nipher NWS 8" AlterNWS 8" unsh Hellmann unshTretyakov

Page 7: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Summary of bias correction in NWT, Canada, 1961-1990

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Cape

Parry

Clinto

n Poin

t

Coppe

rnine

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elian

ce

Fort S

imps

on

Fort S

mith

Nay R

iver

Invik

Norm

an W

ells

Yellow

knife

Eellow

knife

Hyd

ro

Baker

Lak

e

Coral

Harbo

ur

Pelly

BayAler

t

Broug

hton

Islan

d

Cape

Dyer

Cape

Hoope

r

Clyde

Dewar

Lak

es

Eurek

e

Hall B

each

Iqalui

t

Long

staff

Bluf

f

Mao

kar I

nlet

Resolu

te

Byron

Bay

Cambr

idge

Bay

Mou

ld Bay

Sachs

Har

bour

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al p

rec

ipit

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on

(m

m)

measured

corrected

Whitehorse, Yukon, 1948-1994

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archived corrected

Page 8: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

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Months

Pre

cip

ita

tio

n (

mm

)

trace

wind-loss

measuredOverall mean for the NP drifting stations, 1957-90 (Yang, 1999)

Overall mean for 61 climate stations in Siberia, 1986-92 (Yang and Ohata, 2001)0

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trace amount

wind correction

measured

Page 9: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Comparison of Bias Corrections in the High Latitudes

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Siberia Alaska NWT Greenland Arctic basin

Regions

Ra

ng

e o

f y

ea

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rre

cti

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cto

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Page 10: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

a) DIKSON, 73.30N, 80.24E

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thly

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cipi

tatio

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m)

trace amount

wind loss

measured

a) Dikson (73.30N, 80.24E)

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Daily mean w ind speed at 2m (m/s)

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(mm

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Page 11: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Data SourcesDaily precipitation, temperature and wind speed are needed for this

research. • National Climatic Data Center (NCDC), global daily surface data

archive (1994-present) for over 8,000 stations around the world, http://www.ncdc.noaa.gov/cgi-bin/res40.pl

• WMO GTS, the Global Climate Observing System (GCOS) Surface Network (GSN), http://www.wmo.ch/web/gcos/gcoshome.htlm

• Arctic Precipitation Data Archive (APDA) at the Global Precipitation Data Center (GPDC), http://www.dwd.de/research/gpcc/acsys

Page 12: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

• Arctic Ocean (6 hourly and daily) met data collected at the Russian NP drifting station, National Snow and Ice Data Center (NSIDC)

http://www-nsidc.colorado.edu/index.html

Station and gauge info: – type of precipitation gauge– height of gauge and wind sensor– wind shield

WMO and national weather services:– USA, Canada – Russia, Finland, Denmark, ...

Page 13: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Synoptic/climate stations on land above 45N and the Arctic Ocean drifting stations will be used for this research

R ussia

Mongolia

K azakhstan

G reenland

C hina

C anada

Page 14: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Major Task 1: Evaluation and Implementation of the WMO

Bias Correction Methods - threshold wind 6.5m/s

• Analysis of wind regimes over the arctic regions • Focus on winter season and on snowfall days

• Define regions where the WMO bias correction methods may not be appropriate and therefore alternative approaches or further experimental studies should be considered

Page 15: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Major Task 2: Development of Bias-Corrected Arctic

Precipitation Database and Climatology

• Implement the WMO methods to all the stations in the

Arctic regions for last 30 years, 1970-2000???

• Create bias-corrected daily precipitation dataset- an

important basis for analyses of Arctic regional

precipitation, i.e. long-term mean, seasonal cycle, year-

to-year variation, and trend

Page 16: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

• Develop improved precipitation climatology for the Arctic regions

–Consider terrain and the orographic effect on precipitation distribution, use

high-resolution digital elevation models (DEM) to determine elevation, slope,

and aspect of the topography

–Apply PRISM (Daly et al., 1994) and the High-Resolution Weather Data

System (HRWxDS) (Legates et al,. 1999) to generate regional maps of

monthly/yearly bias-corrected precipitation

–Develop gridded precipitation data, use equal-area EASE grid system,

compatible with ACSYS/Arctic Precipitation Data Archive (APDA),

hydrological model intercomparison project, and RS snowcover (SCE/SWE)

products

Page 17: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Major Task 3: Comparison and Validation of the Results

• Compare our results with other precipitation datasets/products, such as Legates and Willmott (1990), Jaeger (1983), UNESCO (1978), Adam and Lettenmaier (2003), and others?

• Compare gauge measurements/corrections with snowcover accumulation in selected regions/basins

• Assess the impact of precipitation bias corrections to regional hydrologic model analyses (Zhang et al., 2000)

• Compare GCM/RCM precipitation simulation with the observed and bias-corrected precipitation fields in selected regions, i.e. Alaska and central Siberia – model simulation agrees better to bias-corrected precipitation

fields particularly in winter months and over windy areas !?

Page 18: Development of Bias-Corrected Precipitation Database and Climatology for the Arctic Regions

Results/Products/Impacts• Practical procedures for correcting gauge-measured precipitation data in the

high latitude regions

• Bias-corrected daily/monthly/yearly (station) precipitation records/correction factors (CF, %) for arctic regions across national boundaries

• Bias-corrected, gridded monthly/yearly regional precipitation data/climatology for the arctic regions

• Impacts: – water balance calculations of both the Arctic Ocean and terrestrial systems – climate change analysis and hydrologic modeling – validation of GCM/RCM simulations – calibration of remote sensing data/products