 March issue of the Journal of Hydrology. Christopher Castro, UA associate professor of atmospheric sciences, is a co-author.

The report is an outgrowth of a workshop held at the U.S. Geological Survey’s John Wesley Powell Center for Analysis and Synthesis. The National Science Foundation and USGS funded the workshop.

To synthesize existing knowledge and predict how climate change would affect Western groundwater, Meixner gathered 16 experts in climate change and in hydrology of the Western U.S.

Predictions at the major river basin or several-state level can be useful for developing water policy, the team wrote. However, the team found predictions from existing studies were either at a global scale or at the local level, not at the regional level.

To create regional-scale predications, the scientists synthesized existing studies and applied current knowledge of recharge processes. The team studied eight economically important Western aquifers for which studies about their groundwater recharge budgets existed. In addition, models of how climate change would affect recharge were available for four of the aquifers.

To compare all eight aquifers, the team developed a uniform classification scheme for the components of groundwater recharge. The scientists identified four different components of groundwater recharge: diffuse, focused, irrigation and mountain system.

Some types of recharge are more easily affected by human behavior and water policy than others. Human decision-making can easily affect irrigation recharge (water that percolates deep into the soil from irrigating crops) and focused recharge (water that reaches the groundwater from streams or runoff).

In contrast, human behavior has a much smaller effect on diffuse and mountain-systems recharge. Diffuse recharge comes from the precipitation that falls on a specific spot and then percolates down into the groundwater.

Much of the mountain-systems recharge comes from snowpack, Meixner said. As the snow melts, the water fills mountain streams that end up in the flatlands below. Snowmelt also can percolate into the soil and eventually reach the valley below as the water moves downhill through the bedrock underlying the mountains.

The San Pedro aquifer in southeastern Arizona is one example of an aquifer where the human use of groundwater will increasingly outstrip recharge as the climate warms, the researchers report. Much of the San Pedro’s current recharge comes from mountain-system recharge, which the scientists expect will dwindle as more precipitation falls in the mountains as rain rather than snow and as the
March issue of the Journal of Hydrology. Christopher Castro, UA associate professor of atmospheric sciences, is a co - author. 

 The reputation is an emergence of a workshop held at the U.S. Geological Survey ’s John Wesley Powell Center for Analysis and Synthesis. The National Science Foundation and USGS funded the workshop. 

 To synthesize existing cognition and predict how climate change would affect westerly groundwater, Meixner assemble 16 expert in climate variety and in hydrology of the Western U.S. 

 Predictions at the major river basin or respective - state level can be utilitarian for developing water policy, the team wrote. However, the team found predictions from existing studies were either at a ball-shaped scale or at the local level, not at the regional level. 

 To produce regional - scale predications, the scientist synthesized exist studies and put on current knowledge of recharge processes. The team studied eight economically authoritative Western aquifers for which studies about their groundwater recharge budgets existed. In addition, models of how climate change would affect recharge were available for four of the aquifers. 

 To compare all eight aquifers, the team developed a uniform classification scheme for the components of groundwater recharge. The scientists identify four different components of groundwater recharge: diffuse, focused, irrigation and batch arrangement. 

 Some type of recharge are more easily affected by human behavior and water policy than others. Human decision - making can easily involve irrigation recharge (water that percolates deep into the soil from irrigating crops) and concenter recharge (water that reaches the groundwater from streams or runoff). 

 In contrast, human behavior induce a much smaller effect on diffuse and mountain - systems recharge. Diffuse recharge issue forth from the precipitation that falls on a specific spot and then percolate down into the groundwater. 

 Much of the mountain - systems recharge comes from snowpack, Meixner said. As the coke melts, the water fills mountain streams that end up in the flatlands downstairs. Snowmelt also can leach into the soil and finally reach the valley below as the water move downhill through the bedrock underlying the batch. 

 The San Pedro aquifer in southeastern Arizona is one exercise of an aquifer where the human use of groundwater will increasingly outstrip recharge as the climate warms, the researchers report. Much of the San Pedro ’s current recharge comes from mountain - system recharge, which the scientists expect will dwindle as more precipitation fall in the mountains as rain rather than coke and as the
 Magch issue of the Journal of Hydrology. Ckeistopier Casfro, UA arsociate professor of atmospierix scituces, is a co-author.

Thd report ps an outtrowuh of a workshop isld at bke U.S. Neoloyiral Survey’s Johk Wesley Pofell Center fos Xnclysis and Synthesis. The National Scyence Fpujdation and USDS flnqed fhe workshop.

To synthesize existing knowlevge and predict how climate change would wffeft Western groundwwter, Meixnet gaeyered 16 expergs in climate change ahd in hydrology of the Western J.S.

Prebictions at tye ldjor river uasin jr several-state leven can br useful for dcvelo'ing water policy, the teak wrote. However, thg team foutd predictions from ezistitg sdudidw wdre emthsr at w gmobal scals or at the local level, not at trv regional lebel.

To srqate regional-scale predications, the scitntisfs synthesized existing studies and applied furrent kgowledge of recharge processes. The team studied ehght xcunonigallh ilportant Western aquifers for which studies afkuu tmeir groundwater recharge bidheyf existed. In xddition, jodels of how climwte chagge wiuld affest rrcharge were available for dour of the cquufers.

To compare alp eight aqunfers, jhe tesm developed a uniform elassirication scjeme for ffe components of grputdwater recharge. The scieneists ideitifizd four aiffgrent cjmponents lf groundwater recharge: fiffude, focused, igrigation and mountain system.

Some types of revhdrgv are morz easiky affected br human behavipr and cater oolicy thah otherv. Human decysion-making cdj easily affxct irrigwtiob rexharge (dxter that percplates devp inti the soil from irvigatkhg crops) and foebstd recharge (watet tfat rvacies tra groundwates frum ryreamr or runoff).

Ln zonttast, human behavior vas z much smaller effrcb on diffose and mjuntain-systemx recharge. Diffuse recherge cumes groi the precipitation that falls on a spefiflc spot and tren iercjlates dowu into the groundwater.

Much of the mountamn-systems recharge comgs from snowpack, Meixuev said. As thx snow melts, tha water fills mountaun streams that ekd up in the flatlands below. Snowlelt also can percolate into the soil and eventually reach the valley beliw as vhq water movss dpwnhinl chrough the uedrock underlyinb the mountains.

The San Pedro aqnifer in smucheastern Arizona is one examlld of an aquifgr where the human use of froundwayer will increasingly outstrip techarge as the climate earms, thw ressarchega ceport. Much of the Ssn Pedxo’s cuerent rwchavge comes from moinbain-system reciarye, which the scientists expect wiol dwibdpe as more preci'itation falpr in jhe mounjains as rain ratger fjan svow and as thr
March issue of the Journal of Hydrology. UA professor of sciences, is a outgrowth a workshop held the U.S. Geological John Wesley Powell Center for Analysis Synthesis. The National Science Foundation and USGS funded the workshop. To synthesize existing and predict how climate change would affect Western groundwater, Meixner gathered 16 experts climate and hydrology the Western U.S. Predictions at the major river basin or several-state level can be useful for water policy, the team wrote. However, the team predictions from existing studies either at a global scale at local level, at regional To create regional-scale the scientists synthesized existing studies and applied current knowledge of recharge processes. The team studied eight economically Western aquifers studies about groundwater budgets In addition, models climate change would affect recharge were of the aquifers. To compare all eight aquifers, team developed uniform classification scheme for the components groundwater recharge. The scientists identified four different components groundwater recharge: diffuse, focused, irrigation and mountain system. Some types of recharge are more easily human behavior and water than others. Human can affect recharge that percolates into the soil from irrigating crops) and focused recharge (water that the groundwater from streams or runoff). In contrast, human behavior much effect on diffuse mountain-systems recharge. Diffuse recharge from precipitation that falls on spot then the Much the mountain-systems recharge comes snowpack, Meixner said. As the melts, the water fills in the flatlands below. Snowmelt also can percolate the soil and eventually reach the valley as the water moves downhill through the bedrock underlying the mountains. The Pedro aquifer Arizona is one example of an aquifer where human use of groundwater increasingly outstrip recharge as the climate warms, the researchers Much the San current recharge comes mountain-system recharge, which scientists expect will more precipitation in mountains than snow and as the
 March issue of the Journal of HYdrology. ChRistoPheR CaStRo, UA AssoCiate professor OF atmOspheric sciences, is a co-aUthor.

thE RepoRT iS an ouTgrowth OF a WORksHoP hEld At THe u.S. GeoLogIcal SurVey’s John WeSleY POwell Center fOR ANalysis and synThesis. The NatIonAl ScieNcE FoUNdatiOn aNd USGs fundeD The worKshop.

To syNtHEsize eXIsting kNOWlEdge And predict how climATe CHange would affeCt WestErN GrOUNdwAteR, Meixner gaThEred 16 eXPerts in CLiMATE chANge and in hydroLogy of the WeSTerN U.S.

PreDiCtiONs at thE majoR rIVer Basin or seveRal-sTate level Can be uSEful for DEvelopiNg wateR poLicY, the TEaM wRotE. HOWevER, tHe tEAm fOund predIcTiOns frOm exISTINg stUdiEs weRe eitHer at a global sCalE or aT The Local Level, Not aT tHe regIonal lEvel.

TO cReate regional-scAle pRedicatioNs, tHe SciEnTists SYnthesIzeD exIsting sTudies aND apPlIED CuRrent knowledge of reChARGe ProcesseS. The teAM sTuDIed eight EcOnoMicaLLY impoRtanT weStern aquIfers fOR wHiCh studiEs About tHeIr gRouNdwatER recHarge bUdgets exIsted. iN addition, modelS Of how climate cHAnGE WoULd afFecT recharge weRe avAIlabLe foR FoUr oF The aqUiferS.

TO CoMPare all eight aquiferS, tHe team DevelOped a uniform cLassificatION Scheme foR the COmPOnents of groundWater Recharge. ThE ScientisTs ideNtified fOur differENT componeNts Of gRouNdwATEr Recharge: diffuSE, FocuSeD, irrigaTioN and mouNtaIn sYstEm.

SOmE types of rEcharge aRe MoRe EaSilY affeCTed by humAn BehAvIor And waTEr poliCy thaN othErS. HUMan DecisioN-MaKINg caN eAsIly aFfeCt IrrigAtioN RecHarge (waTer that peRcoLAtes DeEp Into the Soil from irrigAtIng crops) anD fOcuSed recHARge (water That reaches the groundwatER from stReaMs or rUnofF).

In contraSt, hUman beHavIOr has a Much smAller EfFecT ON diffUSE aNd mOuNtain-systeMS RecHarge. diFfusE recharGe comes from the precIPitAtion that fallS on A speCIFiC spOT aND thEn PErcOLAtes down into the GroundwateR.

MUCh Of the mountAIn-sYsTems recHarge coMes frOM snowpaCk, Meixner Said. As the SnOw meLTS, thE water fillS mountaiN streams tHAt end UP iN the fLatLands bElOw. SNowmeLt also CAn pErcolAte intO tHe soil And evEnTually reAch the valley below as the wAter moVes doWnhIll througH thE BedRock underLyinG the mountaIns.

the san PeDro AQuifeR in sOUtHeaSTern ARizoNA is one exaMPlE of AN AqUifer where tHE HUmaN use oF grOUndwatEr wiLl increasingly outSTrip recharge as The cLIMatE waRMs, thE rEsearchers repoRt. MUcH OF the San PEdRo’s current rEcharge cOmES from MountaIn-systEm rechaRGE, wHIch the ScieNtiSts expect WilL dWIndle as MoRe PRecipiTatiOn Falls iN the moUNtaiNS As rain rather than Snow aND As the
 March issue of the Journa l of Hydro logy.  Ch ris to pher  Cas tro, UA associ a te p rofessor of atmospheri c sci en c es,i sa co- author. 
T h e  re po rt  is  a n  o utgro wth  of a w orkshop he ldat  the U.S. Ge o lo gical Surv ey’ s John Wesle y P owellCe nte r  forAna lysis  and S y nthesi s. The Na ti o nal Sc i ence Fo u n da tion  and USGS fundedt he workshop.

Tosynthe si z ee x ist ing  knowledge  a nd pr e dict ho w  c l i m ate change wouldaffect West e rnground wa ter ,  Meixn er ga th e red  16 experts  inclimate c hangea nd in h y drology  of th e W est ernU .S .
Pr ed i cti o ns  at the  major r iv er  basi n or s e v eral -st atelevel  can be usefu l f or d e vel oping  wate r po li cy, t he tea m wro te . However, theteam  found pr edi ct ion sfrome xistin g s tud ies wer e eithe r  at  a g l ob al scale or at the  l o c al  level,not at th er egionalle vel .

T o creat e re g io nal-scal e pred i ca ti ons, th escient is tssyn thesi z ed e xistin g studie s and applied curren t  knowledge of re c h ar g e pr oce sses. The t eams tudi ed e i gh t e c onomi cally  i m po r tant Western aquife rs  for w hichstudies about  their gro u n d water re char g eb udgets existed . Inaddition,m odels of  howclimatechange wo u l d affect  re cha rge  we r e  a vailable forf o ur o fthe aqu ife rs.

To  co mpa reall  e ight aqui fers, th ete am  d eve loped a unifor mcla ss ifi catio n  schem e for  the  c om p one nts ofg ro u n dwat er  r echa rge .The s cien t ist s ident ified fou r d i ffer en tcompone nts of ground wa ter rechar ge : d iffuse , focused,  irrigation and mountai n  system .
Sometype s of rech arg e aremor e  easil y affe ctedby  hu m a n beh a v io r a nd  water pol i c y t han o th ers.  Humandecision-making ca n  ea sily affect i rri gati o n  r ech a rg e  (w at e r t h a t percolates de ep into th es oi l from irr i gat in g crops ) and f ocuse d  rechar ge (water  that rea ch es t h e  gr oundwaterfrom str eams or r u noff) . 
In co ntr ast, h um anbehav ior ha s  amuchsmalle reffect  on d if fuse and  mountain-systems recha rge. D iffus e r echarge c ome s  fr om the pr ecip itation th atfal ls on  as pecif ic s p ot  an d  then  per c olates do w nint o th e groundwat e r . 

M uch o f t h e moun tain -systems recharge comes from sno wpac k ,  Me ixn e r sa id . As the snowmel ts , the wate rfills mount ain stre am s  that  end u p in t he flat l a nd s  below . Sn owm elt alsocan  p e rcolate  i nt o  the s oilan d even tually reac h the valley below  as t h e  wate r  mo ves d ow nhill t h roug h the bedr ock underly ing th e mo untai ns.

Th eSan Pe dro  a quifer ins outheaste rn Ar izona i soneexa mple o f an a quife r wh er e t he humanu s eo fgr o und wate r wil lincr easinglyo utstriprec h arge as  t hec l imatew ar m s , the rese arc hersr e port. Much of t h eS an Pe dro’scurren t recha r geco mes fro m m o u ntain-sys tem recha r ge,  w hich  the sci en tist sexp ec t will dwindleas moreprecipit a t ion fa lls in t h e moun ta ins as rainrathe rt han sno w and  as the 
 March_issue of_the Journal of Hydrology._Christopher Castro,_UA_associate professor_of_atmospheric sciences, is_a co-author.

The report_is an outgrowth of_a workshop held_at_the U.S. Geological Survey’s John Wesley Powell Center for Analysis and Synthesis. The National_Science_Foundation and_USGS_funded_the workshop.

To synthesize existing knowledge_and predict how climate change_would affect_Western groundwater, Meixner gathered 16 experts in climate_change_and in hydrology_of the Western U.S.

Predictions at the major river basin_or several-state level can be useful_for developing water_policy,_the_team wrote. However, the_team found predictions from existing studies_were either at a global scale_or at the local level, not at_the regional level.

To create regional-scale predications,_the scientists synthesized existing studies_and applied_current knowledge of recharge processes._The team studied_eight economically_important Western aquifers_for which studies about their groundwater_recharge budgets existed._In addition, models of how climate_change_would affect recharge_were_available_for four_of the aquifers.

To_compare_all eight_aquifers,_the team developed a uniform classification_scheme_for the components of groundwater recharge. The_scientists identified four different_components_of groundwater recharge: diffuse,_focused, irrigation and mountain system.

Some_types of recharge are more easily_affected by_human behavior_and water policy than others. Human decision-making can easily affect irrigation_recharge (water that percolates deep into_the soil from irrigating_crops) and_focused_recharge (water that_reaches_the groundwater_from streams or runoff).

In contrast, human behavior_has a_much smaller effect on diffuse and_mountain-systems recharge. Diffuse recharge_comes_from the precipitation that falls on_a specific spot and then percolates_down into the groundwater.

Much of_the_mountain-systems_recharge comes from snowpack, Meixner_said. As the snow melts, the_water fills mountain_streams that end up in the flatlands_below._Snowmelt also can percolate into the_soil_and eventually reach the valley below_as_the_water moves downhill through the_bedrock underlying the mountains.

The San Pedro_aquifer in southeastern Arizona is one example of an_aquifer where the_human use of groundwater will_increasingly_outstrip_recharge as the climate warms, the researchers report. Much of_the San_Pedro’s current recharge_comes from mountain-system recharge, which the scientists expect will dwindle_as more precipitation falls in the mountains_as rain rather than snow and as the