Good research about Global warming

7/28/2019 Good research about Global warming

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Climate changeand impacts

in theEastern

Mediterranean and

the Middle East

A regional climate

assessment by theCyprus Institute


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02 Summary

04 Present climateconditions

05 Climate of the pasthalf millennium:A history of change

06 Future projectionsof climate change:

A hot dry future

07 Air pollution anddesert dust:Changes to airquality

08 Human healthconcerns

09 Land ecosystems andagriculture

10 The Mediterranean Sea:Changes to marineecosystems

11 Changes to

freshwaterresources

12 Energy demand

Contents

The predicted

warming and drying

of the region will havemajor consequences

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The Eastern Mediterranean and theMiddle East (EMME) is made up oftwo dozen countries with over 400million inhabitants spread over anarea with a 2,000 km radius. Afteryears of intense industrialisation,rapid population growth andextensive land conversion, theEMME has now become a globalclimate change hot spot.

Predicted climate changesTo understand the implications ofEMMEs shifting weather patterns,researchers have projected climatechange for the 21st Century, usinga regional climate model basedon an intermediate emissionscenario, and predicted impactson the environment. The researchsuggests substantial regionalclimate changes, with significantlydryer and warmer conditions.

Increasing temperatures

There is expected to be acontinual and gradual warmingof temperatures, with highestrates in the north of the EMME.

The mean temperature rise willbe about 1-3C in the next threedecades, 3-5C by mid-centuryand 3.5-7C by the end of thecentury. This is increasing at

about 0.370.9C per decade,which suggests that the regionis likely to warm at a much fasterrate than the global mean rate of2.8C by the end of the century.

In addition, there are likely tobe extremely high summertemperatures.

Decreasing rain

The precipitation throughout theEMME region is expected to decline.In the north a decrease of 10-50%during the 21st Century is expected,with rainfall primarily decreasing in

spring and summer. In the south,precipitation may actually increasedue to the expanding influence fromthe humid tropics, though this ismodest in absolute terms.

Impacts of theexpected changes

The predicted warming and dryingof the EMME region will have majorconsequences for both humansand natural ecosystems, especially

from the increased heat stress andreduced rainfall.

Impacts on air quality

Air quality is expected to declinein the EMME. In the north,increasing dryness will lead toescalating vegetation fires andresulting pollution emissions. TheEMME has several megacitiesin which air quality is already

seriously degraded and ozonelevels are expected to continueto increase. As a result, air qualitycontrol measures are consideredto be critical.

Summary

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Impacts on human health

There is compelling evidence

that the maximum daytimetemperatures in the EMME areincreasing especially rapidly,which will lead to extended heatwaves with major consequencesfor city dwellers. In addition,vector-borne parasitic and viraldiseases are expected to increasein prevalence. Although increasingtemperatures promote thespreading of vector organisms,hosts and infectious diseases,

it will be necessary to considerclimate change in combinationwith other influences.

Impacts on landecosystems and agriculture

The EMME has a high biodiversitydue to its large gradients intopography and soil fertility, andthe varied climate. The predicteddrying and warming of the EMMEhas the potential to dramatically

alter the balance of species inthe region. Projections suggestthat the milder winters in thenorth will be associated with alengthening of the growing season,which could positively influenceagriculture. However, this will likelybe overshadowed by the increasingnumber of hot days and thedecreasing soil moisture.

Impacts on marine ecosystems

The marine ecosystems of theMediterranean Sea are alreadyaffected by climate-driven and otherhuman-induced changes. There

is expected to be a warming ofwater temperature, increasing saltcontent and resulting in water mass

stabilisation and an expected sealevel rise of about 1.3-2.5 cm perdecade. The marine biodiversity willbe affected by decreased nutrientavailability, marine ecosystemsbecoming more tropical and theinvasion of alien species.

Impacts onfreshwater resources

Parts of the EMME, especially

in the Middle East, are alreadynotorious for fresh water scarcity.The predicted decreasing rainfallwill result in a river dischargedecrease of 10-30% by the end ofthe 21st Century and a significantreduction in the availability offreshwater for the EMME, withimportant social and economicimplications, especially inagricultural areas. The region willneed to invest in desalination andimproved water-use efficiencies.

Impacts on energy demand

Fossil fuels dominate the energysupply in the EMME and this useis growing at one of the highestrates in the world. During thewarm season the demand forair conditioning is expected toincrease significantly. This energydemand will grow in parallel withwater deficits, which additionally

places pressure on energyproduction. Alternative sourcesof energy and improved energyefficiencies are therefore critical forthe EMME region.

Extended heat

waves will

have major

consequencesfor city dwellers

Changing number of dry days/year by mid-century

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The regions climate

The EMME region finds itself ata crossroads of global climaticpatterns. There is a convergence ofdifferent maritime conditions overthe region, extensive adjacent landmasses transporting continentalair and extreme differences intopographical features, all of whichgives EMME its diverse climate.

The importanceof global linkages

The countries within the EMMEare influenced by many of thekey weather tele-connections(linkages of weather anomaliesover great distances). One ofthe most prominent is the NorthAtlantic Oscillation (NAO), whichis a large scale rearrangement ofatmospheric air masses. The ElNio/Southern Oscillation (ENSO)also influences the EMMEs

climate, as El Nio brings dryconditions mainly to the westerncountries.

Apart from the remote and indirectclimate effects NAO and ENSObring, the EMMEs weather isdirectly influenced by the Red Sea

troughs, tropical intrusions and duststorms from the Sahara desert.

The region is also impacted by themassive South Asian monsoon andall the different climatic processesthat control it. This monsoon createslarge-scale subsidence over thecentral and eastern Mediterranean,reducing convection and producingclear skies.

Extreme weather conditions

The current climate experienced

throughout the EMME is alreadyfairly extreme with temperatureand precipitation changing rapidlyacross the region. The northernEMME enjoys a temperateclimate with warm and hot drysummers, occasional droughtsand mild, relatively wet winters.For the southern EMME there islittle rainfall and as a result thesecountries encounter an arid andhot desert-like climate. Since the

EMME region already experienceshot climatic conditions withvarying temperatures anddroughts, there is much concernthat any impacts resulting fromclimate change in this regionwill have disproportional effectscompared to other areas.

Present climate conditions

Increasing daytime summer temperature by mid-century

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Climate pre-1960

In the EMME the seasonality ofrainfall is of major importance tothe pre-1960 climate, with mostfalling in winter. There is an obviousnorthwest-southeast gradient inthe amount of winter precipitation.More pronounced wetter and drierperiods can also be identified in thepre-20th Century period.

Summer temperatures from 1500to around 1900 were not distinctlylower than recent levels. The early

20th Century is characterised by astrong increase in summer meantemperature until around the 1950swhen a cooler period began. Therecords clearly indicate reducedclimate variability prior to the early19th Century.

Climate post-1960

The annual mean temperaturein the EMME region since

1960 ranges from about 0Cin mountainous areas to about15-17C in northern coastal parts.The southern part of the regionhas a notably different regime with

a mean temperature range of 18to 28C. An exceptionally strong,unprecedented warming period isexperienced since the mid-1970s,which includes the hottest summerever recorded in 2003.

The most pronounced post-1960climatic patterns within the EMMEare related to rainfall,regulated bymajor weather systems. The largenorth-south contrast is evidentin both annual and seasonalrainfall patterns. In the northernEMME the average total annual

precipitation between 1961 and1990 ranges from approximately500 mm in the east to more than1,000 mm in the west.

For most of the region, summeris the dry season. In the southernpart of the EMME, rainfalldeficits and summer dryness arecommonplace. The dominance ofdifferences in topography is evidentfrom the localised high winter

precipitation levels. There is alsoclear evidence of a strong dryingtrend starting in the early 1960swith the lowest precipitation ratesbeing recorded in the late 1990s.

Climate of the past half

millennium: A history of change

There is clear

evidence of

a drying

trend starting

in the 1960s

Observed (black) and model calculated (red) temperature trends

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Rising temperatures

Research predicts that thetemperature in the EMME is likelyto increase between 2-4C inwinter and 2-6C in summer over

the coming century. The warmingacross the region will be gradual;ranging from 1-3C in the nextthree decades, to 3-5C in themid-21st Century and to 3.5-7Cby the end of the century.

Declining rainfall

Overall rainfall is predicted todecrease by 20-30% throughoutthe EMMEover the course ofthe 21st Century, although some

areas will see localised thoughmodest increases. In addition,extended periods of more severedroughts are expected in theMediterranean. Precipitationmay significantly decreasein winter along the easternMediterranean coast by between30-50%, although elsewherein the south-eastern MiddleEast there may be increases,though modest in absolute terms

considering the small annualrainfall. In summer, the EMMEdrying is also significant and theareas that will experience winter

rainfall increases are expected tobecome drier in the summer.

More hot days and nights

The overall heat stress in the

EMME region is expected to besignificant in the future with aremarkably large increase in thenumber of hot days per year. Thebiggest increase appears overthe Levant and along the NorthAfrican coast. It is expected thathot nights will gradually increasestarting in the south of the EMMEand progressing north. Theincrease in the number of dayswith hot nights warmer than 25Cby more than 2 months per year

is of particular concern.

Impacts on societyand the economy

In summer, climate change isexpected to intensify heat wavesand this has major implicationsfor human health, energy useand economic activity. TheMiddle East has been identifiedas the first region worldwide to

effectively run out of fresh waterand access to drinking water willbecome a critical issue as parts ofthe EMME essentially dry out.

Future projections of climate

change: A hot dry future

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Increasing fine aerosol particles

There are already high levels ofair pollution in the EMME region,both of natural and anthropogenicorigin. The fine aerosol particlesare mostly composed ofsulphates and particulate organicmatter, whereas the coarserparticles are dominated by desertdust. The levels of fine aerosolparticles in the EMME region areexpected to rise substantiallyduring the mid-21st Century dueto increasing emissions of sulphur

dioxide and nitrogen oxides.

Increasing ozone smog

In summer the EMME is largelycloud-free, and the relativelyintense solar radiation promotesthe formation of ozone. In theMediterranean region,ozonelevels often exceed air qualitylimits, particularly in summer, andthe Mediterranean ozone levels

are among the highest in theworld. It is likely that ozone levelswill continue to increase and thatthe EMME will be a persistingair pollution hot spot withespecially high levels aroundthe Persian Gulf.

Impacts of megacities

Megacities have become acommon phenomenon in theEMME and are a major contributorto air pollution emissions. Sincepopulation growth and urbanisationin the southern and easternparts of the EMME will likelycontinue, the situation of poor airquality is expected to aggravateuntil appropriate measures areimplemented. It is anticipated thatin the long-run, however, trafficemissions will stabilise and could

possibly decrease by the middle ofthe 21st Century.

Impacts of climate change onair quality

The effects of climate changeon pollutant concentrations arerather uncertain. Overall, emissioncontrols (or the lack thereof) areconsidered to have a strongerinfluence on air quality than climate

and land-use changes. In future,the expected increases in warmingand drying will be conducive forozone formation, especially duringheat spells, and this can havemajor consequences for air qualitywithin the EMME.

Air pollution and desert dust:

Changes to air quality

The expectedincreases inwarming anddrying will be

conducive

for ozoneformation

Mediterranean and Middle East hot spot of ozone air pollution

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A recent

upsurge of

vector-borne

diseases has

occurred

There is growing evidence thatpublic health in the EMME regionis already being affected by thechanging climate, and this isexpected to increase in severity.

Increasing frequencyof heat waves

Children and the elderly sufferdisproportionately from extremetemperatures, and the urbanpopulations are particularlyvulnerable. Heat waves can alsoincrease air pollution concentrationsand it is highly probable that heatwaves will become more common

in the EMME. The predictedincrease in occurrence of hotnights in the southern EMME willexacerbate the heat stress and theassociated health issues.

Increasing vector-borneinfectious diseases

After several decades of steadydecline in vector-borne parasiticand viral diseases throughout the

EMME region, a recent upsurgeof these diseases has occurred.Vector-borne diseases are nowspreading northward from Africaand have become an emergingthreat in the EMME.

Malaria This is considered to bea highly climate-sensitive tropical

disease. However, the spreadof Malaria cannot be relatedto a single cause and it will benecessary to study the linksbetween seasonal temperature,rainfall and the vector distribution

West Nile Fever The occurrenceof this virus is connected toclimatic factors, particularlywhere heat stress is enhancedby high humidity. Where coolerclimates currently prevent thefurther spread of the virus,this isexpected to change in future

Leishmaniasis This is the onlytropical disease that has beenendemic to southern Europe for

decades, and studies indicatethat the disease is emerging. Itsspreading is strongly influencedby temperature and humidity

Crimean-Congo HemorrhagicFever It has been suggestedthat the optimum conditionsfor this disease are increasinglyfulfilled in the EMME regionthrough the influence of climatechange on the vegetationstructure

Climate change is not solelyresponsible for the increasingpotential for vector-borne infectiousdiseases in the EMME,but ratherit is a co-factor with several otheraspects such as changes inland-use, agricultural policy andsocioeconomic factors.

Human health concerns

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Impacts on agriculture

Climate conditions in the EMME

allow for a large variety of cropsand fruit to be grown, but somecountries are already almostentirely dependent on irrigation.Overall, the future effects of climatechange on crop production areexpected to be negative, at leastfor the major crops grown in theEMME. This could have importantconsequences for countries witheconomies that are dependent onagricultural production and where

the adaptive capacity is limited.

Increasing growing seasons Climate change can affectagriculture directly through themeteorological conditions thatinfluence crop growth and yield.By the mid-21st Century the lengthof the EMME growing season mayincrease by about one month peryear in the northern EMME

Increasing very hot days Most

importantly for crop cultivation,the occurrence of very hot dayswill increase by two to four weeksper year by mid-century, whichcould seriously damage evenhigh-temperature tolerant cropsgrown in the region

Increasing heavy rain Heavyprecipitation events will increaseby several days per year in

the northern part of EMMEand decrease in southernparts. Further, the increase ofevapotranspiration and thedecrease of soil moisture in dryareas will substantially reduce theland suitability for some majorcrops in the EMME

Decreasing terrestrialbiodiversity

The Mediterranean regionof the EMME is among theworlds highest plant biodiversityareas. However, the threatto biodiversity by extensivehabitat conversion and limitedenvironmental protection hasreached critical proportions. TheMediterranean biodiversity isexpected to suffer the greatestdecrease as a result of climatechange. In the EMME thevegetation currently at the rim of

its natural distribution is expectedto be most sensitive. Theincreased frequency, intensityand duration of extreme climateevents may critically disrupt thebalance between pathogens andvegetation.

Land ecosystems and agriculture

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The Mediterranean Sea is sensitiveto environmental change andresearch has clearly demonstratedsigns of climate-driven change.Marine biodiversity in the EasternMediterranean Sea is thought tobe particularly susceptible to this,with impacts predicted to becomeexasperated even within the next10 years.

Changing circulation patterns

An observed abrupt change inthe Eastern Mediterranean Sea

circulation during the 1990sis attributed to increased saltcontent from less rain, reducedoutflow, less river runoff, coolingfrom severe winters and changesin wind stress. The change incirculation patterns from theseclimatic drivers had a major impacton the marine ecosystems, whichcorroborates their sensitivity toclimate change.

Changing biologicalcharacteristics

Oxygen utilisation rates in thebottom and intermediate waters ofthe Eastern Mediterranean basinincreased twofold following thechange to circulation patterns,probably due to greater availabilityof dissolved organic carbon atthese depths. Mesozooplanktonbiomass nearly doubled andspecies previously found only

in the northernmost margins ofthe Mediterranean Sea suddenlybecame abundant.

Increasing sea levels

The warming of the western andeastern Mediterranean Sea willcontinue to dominate throughoutthe 21st Century with a sea surfacetemperature increase of 2.5-3Cexpected by the end of this century.Warming of both the MediterraneanSeas surface and deep watersis likely to be accompanied byincreases in salt content as well asa sea level change of about 1.3-2.5cm per decade.

Marine ecosystemsbecome more tropical

Climate-driven change in watertemperature, circulation patternsand sea level are anticipated tosignificantly affect ecosystemfunction in the MediterraneanSea over the next century. Higherwater temperatures, reductionin nutrient delivery to the surfacewaters and overall warming of the

Mediterranean Sea ecosystems willbe the first signs of this change.

Increases in invasive species

There will also be movement ofalien species from outside theMediterranean Sea ecosystemsas circulation changes andtemperatures rise, such as invasivemarine organisms travelling throughthe Suez Canal from the Red Sea.Increasing water temperatures will

support the continued invasionof warm water species from theeastern to western basins.

The Mediterranean Sea:

Changes to marine ecosystems

Higher water

temperatures,

reduction in nutrient

delivery to the surface

waters and invasivespecies

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There is little doubt that climatechange is associated with a dryingof subtropical regions, whichincludes the Mediterranean and theMiddle East. Countries in the EMMEregion are already notorious for

water scarcity, and the demands onthese limited water resources frompopulation growth and economicdevelopment are increasing. Thepredicted climate-driven changes ofwarmer temperatures and reducedprecipitation are expected to add tothe existing concerns about wateravailability.

Decreasing riverbasin discharges

The mean annual precipitation inthe EMME will probably declinebetween 10-50% during the 21stCentury, although this decline is notuniform across the region and somecountries in the south will havesmall increases in rainfall levels.

As a result, it is predicted that theaverage annual river discharge ofthe Euphrates, Tigris and JordanRivers could decline by between10-22% by the mid-21st Century,

with continued declines into thelatter part of the century. Suchsignificant precipitation and waterresource decreases will require

important economic and socialadjustment across the region.

Rising water shortages

Some of the EMME countries

already suffer from water scarcity.Population projections combinedwith the predicted internal waterresource availability suggestthat by the mid-21st Century,water shortages will worsen inall countries which are currentlywater scarce. Such changes willnecessitate major adaptation in theagricultural sectors of countries,which currently account for a highpercentage of water use.

Increasing desalination

Extensive desalination isconsidered to be required to meeteven the most basic water needsof EMME countries in the 21stCentury, albeit the potentially costlynature of this solution. Althoughthe climate change effects onwater resources will be significant,they are potentially manageable,although some countries with

comparatively weak economiesmay struggle with the costs ofproviding fresh water throughdesalination.

Changes to freshwater resources

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Changes in energy consumptioncan be linked to the changesin air temperatures and energydemand is closely connectedto both extreme hot and coldweather. Considering the expected

temperature increases across theEMME region, increases in energydemand as a result of climatechange are very likely to occur.

Increasing demandfor air conditioning

Fairly dramatic increases arepredicted in the number of daysthat air conditioning will be requiredin order to provide comfortable

living conditions. By the end of the21st Century, along most of thenorthern Mediterranean coast anadditional 2-3 weeks per year and further inland, up to 5 moreweeks of intense air coolingwill be needed. In North Africa itis expected that more than oneadditional month per year of heavyair cooling will be required. Thesefindings underscore the relativelymajor impact climate change willhave on energy demand.

Decreasing demand for heating

Heating requirements in the EMMEwill also change, especially in winterand to a lesser degree in spring.

The decrease is most evident in thenorthern continental parts of theregion. Given the high temperatureconditions in the southern EMME,the heating requirements are minor.Nevertheless, small decreases

in the winter temperature areprojected in North Africa andthe Middle East, whereas duringother seasons the changes areinsignificant.

Impacts on energy production

The additional energy demandduring the future warm and drysummers happens to coincidewith a deficit in water supply,

which also reduces energyproduction by hydroelectric plantsin the northern EMME. In addition,these conditions will occur atthe same time as a growingdemand for desalinated water.In EMME countries with limitedresources, there is expected to bean increasing disparity in powersupply, and a growing need forinnovative solutions such as theco-generation of electricity anddesalinated seawater by using solar

power. Even though changes indemand for heating will to somedegree compensate in terms ofenergy use, they are unlikely to helpsolve the growing problems withenergy supply.

Energy demand

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