Response of Western Mountain Ecosystems to Climatic Variability and Change: A Collaborative Research Approach - Ecological Consequences of Climate Change - page 164

approaches.. Modeled. projections. of. the. consequences. of. natural. ire,. prescribed.
ire,. and. timber. harvest. provided. insight. on. the. effects. of. potential. management.
options.in.the.context.of.climatic.change.
n orThern r oCky m ounTains
Research.has.been.conducted.mostly.in.Glacier.NP.(Montana)..An.integrated.pro-
gram.of.mountain.ecosystem.modeling.and.empirical.studies.has.quantiied.ecologi-
cal.processes. and. biodiversity.patterns. affected.by.climatic. variability..Ecosystem.
models.have.been.used.to.quantify.snow.distribution,.annual.watershed.discharge,.
and.stream.temperature.variation.under.the.warmer,.wetter.climate.projected.for.this.
region..Interannual.variation.in.snowpack.is.closely.related.to.the.Paciic.Decadal.
Oscillation.and.modiies.ire.cycles.through.its.effects.on.fuels..Glaciers.are.rapidly.
disappearing.from.Glacier.NP..In.1850,.there.were.150.glaciers,.but.today.there.are.
only.37,.and.simulation.models.predict.that.all.glaciers.in.the.park.will.be.gone.by.
2030.at.current.warming.rates..Modeling.indicates.that.in.a.warmer.climate.high-
elevation.conifer.productivity.will.decrease.but.alpine.vegetation.productivity.will.
increase..Modeling.also.suggests.that.low-elevation.forests.will.be.more.productive.
but.generate.higher.fuel.loads.that.contribute.to.high-intensity.wildires.
C enTral r oCky m ounTains
Research. has. been. conducted. mostly. in. Rocky. Mountain. NP. (Colorado)..
Paleoecological,. experimental,. remotely. sensed,. modeling,. and. monitoring. tools.
have. bounded. the. range. of. ire. and. insect. outbreaks. over. the. past. 400. years. and.
correlated.these.with.El.Nĩo-Southern.Oscillation.events..Tree-line.expansion.into.
tundra.has.not.occurred.since.the.mid-1800s,.although.changes.in.growth.form.from.
krummholz. to. upright. trees. have. occurred.. Late-successional. coniferous. forests.
are.vulnerable.to.changes.in.disturbance.regimes.rather.than.directly.responsive.to.
changing.climate..Aspen.forests—systems.with.high.plant.and.insect.diversity—are.
sensitive.to.ire.suppression.(which.allows.conifers.to.establish).and.high-intensity.
ires.(which.allow.exotic.species.to.establish)..Simulations.of.stream.discharge.and.
ecosystem. processes. show. that. the. timing. of. snowmelt,. but. not. water. volume,. is.
sensitive. to. warming.. Recent. observations. also. show. that. spring. snowmelt. is. not.
occurring.earlier.at.high.elevations,.but.summer.discharge.is.increasing.as.a.result.
of.increased.summer.temperatures.and.melting.glaciers.and.permafrost..Regional.
climate.has.responded.to.changes.in.land.use.that.add.moisture.to.the.atmosphere.
near.mountains.
s ouThern r oCky m ounTains
Research.has.been.conducted.mostly.in.Bandelier.National.Monument.and.adjacent.
landscapes.in.northern.New.Mexico.and.southern.Colorado..Studies.have.focused.on.
the.sensitivity.of.semiarid.forests.and.woodlands.to.climatic.change.by.(1).quantifying.
patterns.of.drought-related.tree.mortality.and.associated.ecotone.shifts,.(2).inferring.
long-term. relationships. between. climate. and. severe. ire. events,. and. (3). measuring.