Geoscience Reference
In-Depth Information
TABLE 9.1
Full Site Names and Abbreviations for the LTER Sites Used
in This Chapter
Site Abbreviation
Full Site Name and Location
AND
Andrew.Forest.LTER,.Oregon
ARC
Arctic.LTER,.Alaska
BNZ
Bonanza.Creek.LTER,.Alaska
CDR
Cedar.Creek.LTER,.Minnesota
CWT
Coweeta.Forest.LTER,.North.Carolina
HBR
Hubbard.Brook.LTER,.New.Hampshire
HFR
Harvard.Forest.LTER,.Massachusetts
JRN
Jornada.Basin,.New.Mexico
KBS
Kellogg.Biological.Station.LTER,.Michigan
KNZ
Konza.Prairie.LTER,.Kansas
LUQ
Luquillo.LTER,.Puerto.Rico
NTL
North.Temperate.Lakes.LTER,.Wisconsin
NWT
Niwot.Ridge.LTER,.Colorado
SEV
Sevilleta.LTER,.New.Mexico
SGS
Short.Grass.Steppe.LTER,.Colorado
VCR
Virginia.Coast.Reserve.LTER,.Virginia
1995)..It.is.indexed.by.the.difference.in.sea-level.pressure.between.stations.
at. Gibraltar. and. Iceland.. Physically,. it. represents. east-west. oscillations. in.
the.position.of.the.Icelandic.Low.and.Bermuda.High.semipermanent.pres-
sure.centers..Fluctuations.in.the.NAO.area.are.associated.with.changes.in.
the. position. and. strength. of. the. upper-air. westerly. low. in. the. Northern.
Hemisphere,.which.in.turn.inluence.patterns.of.temperature.and.pressure.
over.the.major.northern.land.masses..Although.the.effects.of.the.NAO.are.
most.prominent.in.Europe,.NAO.can.affect.climate.in.the.North.American.
interior,.producing.warmer.winters.when.the.NAO.index.is.high.(van.Loon.
and. Rogers. 1978).. Amplitude. and. phase. of. the. NAO. are. highly. variable,.
with. variations. at. both. interannual. and. interdecadal. time. scales. (Hurrell.
1995)..NAO.index.values.were.obtained.from.the.NWS.Climate.Prediction.
Center.(http://www.cpc.noaa.gov/products/precip/CWlink/pna/nao.shtml).
.
3..
Paciic North American Pattern (PNA).
The.PNA.is.a.teleconnection.pat-
tern. characterized. by. low-frequency. (≈30. year). variability. in. extratropi-
cal. Northern. Hemisphere. pressure.. PNA. indices. are. calculated. from. a.
weighted. combination. of. normalized.differences.of. 500.hPa.geopotential.
height.values.at.4.latitudes.(Wallace.and.Gutzler.1981)..The.PNA.is.closely.
associated.with.upper.air-low.over.North.America;.positive.values.of.the.
PNA.index.indicate.zonal.low.in.the.upper.air.westerlies,.whereas.nega-
tive. (or. reverse). values. indicate. meridional. low.. These. alterations. in. the.
upper-level. low. translate. into. variations. in. temperature. and. precipitation.
at.the.surface..During.the.positive.or.warm.PNA.phase,.precipitation.shifts.
