sea$level$change$climate.socialsciences.hawaii.edu/courses/geog401... ·...
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Sea$Level$Change$
Chip$Fletcher$
Temperature$history$
Paleothermometry Oxygen isotopes 18O/16O; temp. dependent, high values mean low temperatures (precip and seawater)
Mg/Ca; easier to uptake in high temperatures, ocean values essentially unchanging Sr/Ca; Sr inversely varies with SST Leaf Physiognamy; size, toothed edges, drip tips Nearest living relative analogy Deuterium; heavy hydrogen precipitates early Organic compounds change configuration with temperature (alkenones, amino acids) Pollen, etc. Paleosol carbon Atmospheric carbon dioxide content
Jouzel$et$al.,$Orbital$and$millennial$Antarc@c$climate$variability$over$the$past$800,000$years,$Science$10$August$2007:$Vol.$317$no.$5839$pp.$793K796$DOI:$10.1126/science.1141038;$$$
C02$levels$at$400$ppm$
Paleo$Sea$Level$–$indirect$proxies$
• Eccentricity$–$100,000$&$400,000$yrs$
Orbital$changes$occur$over$thousands$of$years,$and$the$climate$system$may$also$take$thousands$of$years$
to$respond$to$orbital$forcing.$
! Obliquity$–$$$$$$$41,000$yrs$
• Precession$–$23,000$yrs$
During'the'Last'Interglacial,'Climate'Was'Warmer'
and'Sea'Level'Higher'than'at'Present.'
Warmer
Colder
+6.6$m$above$present$ Kopp et al. Probabilistic
assessment of sea level during the last interglacial stage. Nature, 2009; 462
(7275)
0
2
-2
4
6
80°S 40°S 0° 40°N 80°N
ΔT (°
C)
Eemian$Temperature$and$Sea$Level$
Red$dots$–$temperature$(sea$surface,$ice$cores,$pollen)$Green$line$–$model$of$temperature$data$Blue$–$B1,$2100$scenario,$1.1#2.9oC(
Clark,$P.U.,$and$Huybers,$P.,$2009,$Interglacial$and$future$sea$level:$Nature,$v.$462,$p.$856K857.$
Sea level was +6.6 m (95%) higher than today
Kopp et al. Probabilistic
assessment of sea level during the last interglacial stage. Nature, 2009; 462
(7275)
2015'
Jan.'2016'
Feb.'2016'
The$end$of$stable$climate$
12,000' 8,000' 4,000' Today'
H6oC'
H2oC'
'0oC'
'2oC'
'6oC' $$$$$$
2oC'H'Paris'Accord'
$$$$$$$4oC'–'Large'regions'too'hot'to'support'life'
$$$$$$
6oC'–'60H70%'exPncPon,'O
2'decrease'
Sekerci, Y. and Petrovskll (2015) Mathematical modeling of Plankton-Oxygen dynamics under the climate change. Bulletin of Mathematical Biology: DOI 10.1007/sl11538-015-0126-0
16,000'20,000'24,000'
H4oC'
'4oC'
Ice$Age$
Current$Interglacial$
Cau@ous$Op@mism$About$Climate$Change$• Last$year$a$record$$286$billion$was$invested$worldwide$in$new$renewable$
energy,$twice$as$much$as$in$coal$and$gasKfired$power$plants.$• US$use$of$coal$has$dropped$16%$in$past$decade$
• Cost$of$solar$power$has$fallen$75%$in$5$yrs$• 84%$of$Americans$support$clean$energy$
• California$requires$that$all$homes$be$net$zero$by$2020$and$businesses$by$2030$
• China$is$inves@ng$$16$billion$in$Ev$car$infrastructure$• India$is$moving$400$million$people$to$solar$
• Sweden$now$recycles$99%$of$household$waste$• The$UK$government$announced$it$will$end$coal$power$by$2025$
• Divestment$campaigns$have$led$to$$2.6$trillion$divested$out$of$fossil$fuel$companies$
• COP21$provides$a$framework$for$global$ac@on$
UK$–$AVOID$Project:$$hip://www.avoid.uk.net/indcs/$Jackson,$R.B.,$et$al.,$2016,$Reaching$Peak$Emissions.$Nature$Climate$Change,$v.$6,$January.$
Stopping$by$1.5$to$2oC?$• We$have$a$long$way$s@ll$to$go$
– 2015$CO2$growth$largest$ever$– Na@ons$current$pledges$will$lead$to$3oC$warming$– Most$technical$experts$dispute$that$1.5oC$is$aiainable$(requires$CO2$removal).$
– Even$a$90%$cut$in$current$emissions$by$2025$is$insufficient$to$limit$warming$to$2oC.$
– $Emissions$through$2015$already$have$locked$in$1.7$m$(up$to$3.7$m)$of$global$SLR.$$
Sea'level'+3'T'
Gasser, T. et al. (2015) Negative emissions physically needed to keep global warming below 2oC.. Nature Commuications 6. 7958: http://www.nature.com/ncomms/2015/150803/ncomms8958/full/ncomms8958.html
Clark, P., et al., 2016. Consequences of twenty-first-century policy for multi-millennial climate and sea-level change, Nature Climate Change , advance on-line publication: doi:10.1038/nclimate2923
Sea$Level$Rise$• NASA$December,$2015$
– “Given$what$we$know$now$about$how$the$ocean$expands$as$it$warms$and$how$ice$sheets$and$glaciers$are$adding$water$to$the$seas,$it's$preiy$certain$we$are$locked$into$at$least$3$feet$[0.9$meter]$of$sea$level$rise,$and$probably$more.”$
• Coastal$erosion$$• Wave$flooding$$• Groundwater$inunda@on$$• Drainage$failure$$• Hurricane$and$tsunami$vulnerability$
The$worlds$ice$is$mel@ng$
Greenland$is$mel@ng$
West$Antarc@ca$is$collapsing$
NBC$news$West$Antarc@c$collapse$
M.$Zemp,$et$al.$J.$Glaciology,$61,$p.$745K762,$2015$
Today$the$oceans$absorb$heat$at$twice$the$rate$they$did$18$yrs$ago$
Cheng L. J. Zhu, and J. Abraham, 2015: Global upper ocean heat content estimation: recent progress and the remaining challenges. Atmospheric and Oceanic Science Letters, 8. DOI:10.3878/AOSL20150031. Glecker, P.J., et al. (2016) Industrial era global ocean heat uptake doubles in recent decades. Nature Climate change. doi:10.1038/nclimate2915
Over$90%$of$the$heat$trapped$by$greenhouse$gases$since$the$1970s$is$in$the$oceans$
TopexKPoseiden$Satellite$
1.2 mm/yr $$
$$
$$$$$$$
4.4 mm/yr (2010-2015)
Hansen$et$al.,$2015;$Church$and$White,$2011;$Nerem$et$al.,$2010;$Hay$et$al.,$2015;$Yi$et$al.,$2015$$$
0.6 mm/yr (1900-1930)
1.2 mm/yr (1930-1992)
3.3 mm/yr (1993-2015)
IPCC,$AR5,$2013$
Research$used$the$upper$bound$sea$level$model$under$RCP8.5$from$
IPCC–$AR5$(2013)$
Equatorial$Pacific$may$experience$seaKlevel$heights$10$to$20%$greater$than$the$global$mean$(IPCCKAR5,$2013)$$
Sea$level$rise$will$not$stop$at$2100$
Levermann$et$al.,$2013$The$mul@millennial$seaKlevel$commitment$of$global$warming,$PNAS,$110.34,$13745K13750$$Clark,$P.,$et$al.$(2016)$Consequences$of$twentyKfirstKcentury$policy$for$mul@Kmillennial$climate$and$seaKlevel$change.$Nature,$$$PUBLISHED$ONLINE:$8$FEBRUARY$2016$|$DOI:$10.1038/NCLIMATE2923$$$$
3$m$10$w$
6$m$20$w$
Groundwater$Inunda@on$
Rotzoll,$K.,$and$Fletcher,$C.$in(press,$Assessment$of$groundwater$inunda@on$as$a$consequence$of$seaKlevel$rise.$Nature$Climate$Science$
Storm$drains$back$up$at$high$
@de.$
High$Tide,$Miami$K$$400$M$in$pumps$and$cisterns$
Coastal'Erosion'
Today$70%$of$Hawaii's$beaches$are$chronically$eroding$
This$will$increase$to$92%$by$2050$and$nearly$100%$by$2100$
Erosion$could$reach$200$w$under$3$w$of$SLR$(5$x$the$current$setback)$
End$of$the$Century$sea$level$rise$
Sta@c$+$Groundwater$Inunda@on$4.0$w,$2100$
Coastal$Erosion$2100$
80%$erosion$boundary,$2100$
80%$erosion$boundary,$2030,$2050,$2075,$2100$
Ewa$Beach$–$Wave$Inunda@on$
Present$day$
2030$
Ewa$Beach$–$Wave$Inunda@on$
2050$
Ewa$Beach$–$Wave$Inunda@on$
2075$
Ewa$Beach$–$Wave$Inunda@on$
2100$
Ewa$Beach$–$Wave$Inunda@on$
Ewa$Beach$–$Wave$Inunda@on$(4w)$
4$w$
