Annexes | INTERNATIONAL COURT OF JUSTICE

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INTERNATIONAL COURT OF JUSTICE

OBLIGATIONS CONCERNING NEGOTIATIONS RELATING TO

CESSATION OF THE NUCLEAR ARMS RACE AND TO NUCLEAR
DISARMAMENT
(Marshall Islands v. India)

ANNEXES TO

MEMORIAL
OF

THE MARSHALL ISLANDS

16 DECEMBER 2014 LIST OFA NNEXES

Annex 1 – The 2014 Report on the Effects of Regional Nuclear Fallout Between
India and Pakistan. Report by: Michael J. Mills, Owen B. Toon, Julia Lee-Taylor, and
Alan Robock, “Multidecadal Global Cooling and Unprecedented Ozone Loss
Following a Regional Nuclear Fallout”, in Earth’s Future.

Annex 2 – The Map Series Demonstrating the Global Spread of Smoke from a

Regional Nuclear Fallout Between India and Pakistan, and Selected Maps from the
2014 Report Submitted as Annex 1

Annex 3 – The Republic of India’s Letter to the Court of 6 June 2014

Annex 4 – The Republic of India’s Letter to the Court of 10 June 2014

Annex 5 – The Republic of India’s Article 36 para. 2 Declaration

Annex 6 – The Republic of the Marshall Islands Article 36 para. 2 Declaration ANNEX1

THE2014R EPORT ON THEFFECTS OREGIONALN UCLEARFALLOUTB ETWEEN
INDIA ANPAKISTAN.REPORT B:M ICHAELJ.MILL,OWEN B.TOON ,ULIALEE-
TAYLOR,ANDALAN ROBOCK,“M ULTIDECADALGLOBALC OOLING AND

UNPRECEDENTEDO ZONELOSSF OLLOWING R EGIONALNUCLEARF ALLOUT”.Earth’sFuture

RESEARCH ARTICLE Multidecadal global cooling and unprecedented ozone loss

10.1002/2013EF000205
following a regional nuclear conﬂict

Key Points: Michael J. Mills, Owen B. Toon, Julia Lee-Taylor, and Alan Robock 3

• Impacts of a regional nuclear war1are 2
simulated with an Earth system NCAR Earth System Laboratory, Boulder, Colorado, USAa,boratory for Atmospheric and Space Physics and
model Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, Colorado, USA,
•Globalcoolingfollowingaregional 3Department of Environmental Sciences, Rutgers, State University of New Jersey, New Brunswick, New Jersey, USA
nuclear war could persist for more
than 25years
•Globalozonelossunprecedentedin
human history is conﬁrmed Abstract We present the ﬁrst study of the global impacts of a regional nuclear war with an Earth sys-

tem model including atmospheric chemistry, ocean dynamics, and interactive sea ice and land compo-
nents. A limited, regional nuclear war between India and Pakistan in which each side detonates 50 15kt
Corresponding author:
M. J. Mills, [email protected] weapons could produce about 5Tg of black carbon (BC). This would self-loft to the stratosphere, where
it would spread globally, producing a sudden drop in surface temperatures and intense heating of the

Citation: stratosphere. Using the Community Earth System Model with the Whole Atmosphere Community Cli-
Mills, M. J., O. B. Toon, J. Lee-Tamate Model, we calculate an e-folding time of 8.7years for stratospheric BC compared to 4–6.5years for
A. Robock (2014), Multidecadal global
cooling and unprecedented ozone lossrevious studies. Our calculations show that global ozone losses of 20%–50% over populated areas, lev-
els unprecedented in human history, would accompany the coldest average surface temperatures in the
following a regional nuclear conﬂict,
Earth’s Future, 2,161–176, last 1000years. We calculate summer enhancements in UV indices of 30%–80% over midlatitudes, sug-
doi:10.1002/2013EF000205. gesting widespread damage to human health, agriculture, and terrestrial and aquatic ecosystems. Killing

frosts would reduce growing seasons by 10–40days per year for 5years. Surface temperatures would be
Received 30 SEP 2013 reduced for more than 25years due to thermal inertia and albeﬀd ects in the ocean and expanded sea
Accepted 31 JAN 2014
Accepted article online 7 FEB 2014 ice. The combined cooling and enhanced UV would put signiﬁcant pressures on global food supplies and
Published online 1 APR 2014 could trigger a global nuclear famine. Knowledge of the impacts of 100 small nuclear weapons should

motivate the elimination of more than 17,000 nuclear weapons that exist today.

1.Introduction

In the 1980s, studies of the aftermath of a global nuclear conﬂict between the United States and the
Soviet Union predicted that airborne particles, such as ﬁne soil and smoke resulting from explosions

and ﬁres, could circle the globe, producing “twilight at noon,” and cooling the surface for years, in what
became known as “nuclear winterC ”r[utzen and Birk,s1982;Turco et a.l, 1983;Pittock et a.l, 1985]. Fur-

ther studies looked at perturbations to atmospheric chemistry, predicting that odd nitrogen produced
by the largest nuclear weapons could loft to the stratosphere, resulting in signiﬁcant ozone loss, and an

“ultraviolet spring” to followa[tional Research Counc,i1l985;Stephens and Birk,s1985]. Leaders in the
United States and the Soviet Union became aware of the global environmental damage of nuclear war

and subsequently negotiated treaties that have signiﬁcantly reduced their nuclear stockpiles from their
peak near 65,000 in 1986 to less than 20,000, a decline that continues with further negotiations in recent

years [Robock et a.l, 2007a;Toon et a.,l2007, 2008]. Nevertheless, signiﬁcant numbers of weapons remain,
and the number of nuclear-armed states continues to increase.

Since 2007, studies have revisited the issue of global nuclear conﬂicts with modern global climate mod-

els, conﬁrming the severity of the climatic impacts that had been predicted with simple climate models
or with short simulations of low-resolution atmospheric general circulation models in the 1R 9o80sc[k

et al., 2007a], and raising new concerns about severe global climatic impacts of regional nuclear conﬂicts
[Robock et a.l, 2007b;Toon et a.,l2007;Mills et al., 2008;Stenke et a.l, 2013]. Even the smallest of nuclear
This is an open access article under
the terms of the Creative Commons weapons, such as the∼15kt weapon used on Hiroshima, exploding in modern megacities would pro-
Attribution-NonCommercial-NoDerivs duce ﬁrestorms that would build for hours, consuming buildings, vegetation, roads, fuel depots, and other

License, which permits use and distinfrastructure, releasing energy many times that of the weapon’s yiT eolo[ et a.,l2007].Toon et a.[l2007]
bution in any medium, provided the estimated the potential damage and smoke production from a variety of nuclear exchange scenarios,
original work is properly cited, the use
is non-commercial and no modiﬁca- and found that smoke would initially rise to the upper troposphere due to pyroconvecRto ibno.ck et a.l
tions or adaptations are made. [2007b] examined the climatic impact of the smoke produced by a regional conﬂict in the subtropics in

which two countries each used 50 Hiroshima-size (15 kt) nuclear weapons, creating such urban ﬁrestorms.
Using the global climate model GISS ModelE (Goddard Institute for Space Studies, New York), they cal-
culated that nearly all the 5 Tg of smoke produced would rise to the stratosphere, where it would spread
∘ ∘
globally, reducing the global average temperature by 1C .2for 3–4 years and by more than 0.C 5for
adecade.Thise ﬀect was longer lasting than that found in previous “nuclear winter” studies, because

older models could not represent the rise of smoke into the stratosphM eils. et a.l [2008] then used
achemistry-climatemodeltocalculatethattheconcurrentheatingofthestratospherebyupto100 ∘C
would produce global ozone loss on a scale unprecedented in human history, lasting for up to a decade.

Recently,Stenke et a.l[2013]usedathirdindependentmodeltoconﬁrmthemajorﬁndingsofthesetwo

previous studies. That study used the chemistry-climate model SOCOL3 to assess impacts on climate and
stratospheric ozone for a range of inputs and particle sizes. The study coupled a mixed-layer ocean with

adepthof50mandathermodynamicseaicemoduletoahigh-topatmosphericmodel,whichcalcu-
lated chemistry eﬀects in agreement with Mills et a.l[2008].UnlikRobock et a.l[2007b],thestudydidnot

consider active ocean dynamics, and hence could not incorporate the clim ﬀaetcetseof changing ocean
circulation. The inclusion of only the top 50m of ocean limits the thermal ineﬀ rteas that occur in the
presence of a deep ocean, making surface temperature responses too rapid, as the heat content of the

deeper ocean is not considered.

Here we present the ﬁrst study of this scenario with an Earth system model, coupling a chemistry-climate
model to interactive ocean, sea ice, and land components.

2.ModelDescription

2.1. CESM1(WACCM)
We revisit the scenario of nuclear war between India and Pakistan, each side using 50 Hiroshima-size

weapons in megacities on the subcontinent, using the ﬁrst version of NCAR’s Community Earth System
Model (CESM1), a state-of-the-art, fully coupled, global climate model, conﬁgured with fully interactive

ocean, land, sea ice, and atmospheric componenH tsur[rell et a.l, 2013]. For the atmospheric component,
we use the Whole Atmosphere Community Climate Model, version 4 (WACCM4), which is a superset of

version 4 of the Community Atmospheric Model (CAM4), and includes all the physical parameterizations
of that modelN [ eale et a.l, 2013]. WACCM is a “high-top” chemistry-climate model that extends from the
surface to 5.1×10 −6hPa (∼140km). It has 66 vertical levels and horizontal resolution of 1latitude×2.5 ∘

longitude. WACCM includes interactive chemistry that is fully integrated into the model’s dynamics and
physics. Heating the stratosphere, for example, feeds back onto chemical reaction rates. Photolysis rates

are calculated based on extinction of exoatmospheric ﬂux from overhead ozone and molecular oxygen,
and are unaﬀected by aerosol extinction. WACCM uses a chemistry module based on version 3 of the
Model for Ozone and Related Chemical Tracers (MOZARK Ti)n[nison et a.l, 2007], tailored to the middle

and upper atmosphere. The chemical scheme includes 59 species contained in the O x,NO xHO ,xlO , x
and BrO chemical families, along with CHand its degradation products; 217 gas-phase chemical reac-
x 4
tions; and heterogeneous chemistry that can lead to the development of the ozone hole. For our simula-
tions, CESM1 includes the active land, ocean, and sea ice components describeLd abyrence et a.l[2011],

Danabasoglu et a.l[2012], andHolland et a.l[2012], respectively. The full ocean model extends up to
5500m in depth, and includes interactive, prognostic ocean circulation. The nominal latitude-longitude
resolution of the ocean and sea ice components ,itshe 1sameasinCESM1(WACCM)simulationscon-

ducted as part of phase 5 of the Coupled Model Intercomparison ProM jeatrs[h et a.l, 2013].

2.2. CARMA

We have coupled WACCM with version 3 of the Community Aerosol and Radiation Model for Atmospheres
(CARMA3), a ﬂexible three-dimensional bin microphysics package that we have adapted for the treat-

ment of black carbon (BC) aerosol. This allows the BC to experience gravitational settling, and obviates
the implementation of molecularﬀ duision, which the gas-phase tracers in WACCM experience at high

altitudes. CARMA originated from a one-dimensional stratospheric aerosol code developT eudrcboyet a.l
[1979] andToon et a.[1l979]thatincludedbothgas-phasesulfurchemistryandaerosolmicrophysics.
The model was improved and extended to three dimensions as describe Toobnyet a.l[1988]. Extensive

updates of the numerics continue to be made. For this study, we limit BC to one size bin of ﬁxed radius.

As described below, we performed an ensemble of runs assuming a microphysical radius of 50nm, to be

consistent with the optical properties of BC assumed in the model’s radiative code, which are derived from
the Optical Properties of Aerosols and Clouds (OPAC) software packa Hess[et a.l, 1998]. Our previous

studies of BC in the stratosphere from nuclear war and space tourism used these same optical properties,
but with a radius for sedimentation that was twice as lageill[s et a.l, 2008;Ross et a.l, 2010]. We also con-
ducted one perturbation run using the same 100nm radius for sedimentation as those previous studies,

for comparison in the coupled model.

We do not allow calculated particle populations to change radiatively or microphysically other than by
rainout, sedimentation, and transport. The particles are assumed to be completely hydrophilic from the
−3
start, and hence are subject to rainout in the troposphere. We assume a mass density of 1gcmfor each
BC particle, consistent with measurements of atmospheric BC particles collected on ﬁlters, which are com-
posed of smaller, denser particles aggregated in fractal formations with spatial Hass [t a.l, 1998].

AsToon et a.l[2007] point out, coagulation of BC is likely to form chains or sheets, which would have the
same or higher mass absorption co ﬃecients as smaller BC particles. Drag forces would decrease sedimen-

tation of such chains or sheets compared with aerosols that grow as simple spheres. Our neglect of coag-
ulation, assuming a monodisperse distribution of 50 nm radius spheres, should more accurately predict
stratospheric lifetime under conditions with fractals than a treatment of growth into larger spheres with

faster sedimentationT.oon et a.l[2007] also indicate that the BC is likely to become coated with sulfates,
organics, and other nonabsorbing materials, which could act as lenses, refracting light onto the BC. This

eﬀect might increase absorption b∼ y50%, leading to potentially greater impacts than those we modeled.

2.3. Model Setup

We have performed an ensemble of three “experiment” runs initialized with 5Tg of BC with 50nm radius
over the Indian subcontinent. A fourth experiment run includes the same mass and spatial distribution
of BC, with 100 nm sedimentation radius. We compare these experiment runs to an ensemble of three

“control” runs without this additional BC. Each of these seven runs simulated the time period from 1 Jan-
uary 2013 to 1 January 2039, with concentrations of greenhouse gases and other transient constituents

changing with time according to the speciﬁcations of the “medium-low emissions” Representative Con-
centration Pathway (RCP4.5) scenariM oe[inshausen et a.,l2011], a baseline for climate projections. We
also tried starting the simulated conﬂict on 15 May, as was doneRbbyock et a.l[2007b] andStenke et a.l

[2013], and found that the ﬀi rent season did not signiﬁcantlyﬀect the stratospheric distribution or cli-
matic impact of the BC. Because of the prolonged surface cooling that we calculated, we extended our

runs beyond the 10year span used in previous studies to 26 years.

In the experiment runs, 5Tg of BC was added to the initial atmospheric condition in a constant mass mix-
ing ratio of 1.38×106 kg/kg air between 300 and 150hPa in a horizontal region spanning 50 adjacent
model columns roughly covering India and Pakistan. The BC heats the atmosphere to extreme conditions,

requiring a reduction of the model’s standard time step from 30 to 10min. Because this reduction in time
step produces a signiﬁcant increase in cloudiness in the model due to dependencies in the cloud param-

eterization, we reduced the time step consistently in the experiment and control runs. We also tried an
alternate approach of increasing the dynamical substepping in the model, but found that the 16-fold

increase in the number of substeps required to produce a stable result produced a similar increase in
clouds to our original approach. We diagnose thﬀ eects of reducing the model time step in section 2.4.

The three members of each ensemble were conﬁgured wiﬀ tereint initial conditions for the ocean, land,
and sea ice components, derived from the ensemble of three RCP4.5 CESM1(WACCM) runs conducted

as part of CMIP5M[ arsh et a.l, 2013]. These components interact with the atmosphere, producing a
representation of natural climate variability among the three runs in each ensemble. As we will show,

the variability that we calculate within each ensemble is small compared to tﬀheedices between the
experiment and control ensemble averages, indicating that tﬀ heecets we calculate are not attributable to
model internal variability.

2.4. Model Validation
To understand thﬀ eeects of changing the model time step on our conclusions, we diagnosed the cli-

mate of one of our control runs for years 2023–2038, 16 years starting 10 years after the change in time

step, with reference to the climate of the same years from one of the CESM1(WACCM) CMIP5 runs for
RCP4.5, the same forcing scenario used in our runs. Tﬀhecteof increased low clouds is to change the
global shortwave (SW) cloud forcing fro−m55 to−62 Wm −2.ObservationsfromCloudsan’Radi-s

ant Energy Systems (CERES) Energy Balanced and Filled (EBAF) put this forcin− g51eWarm−2,sothe
change produces a more reﬂective planet than is observed (A. Gettelman, personal communication). This

may lead to an underestimation of the surface cooling anomaly in our calculations, becau ﬀseectthe e
of extinction in the stratosphere would be reduced if less SW radiation reaches the surface in both our
−2
control and experiment runs. At the same time, global longwave cloud forcing increases from 30 Wm
in our CMIP5 run to 34 Wm.ObservationsfromCERESEBAFputthisforcingnear26–27Wm −,sothe
change is toward more greenhouse warming from high clouds than is observed. This 4 Wm −2increase in

cloud forcing partiallysets the surface coolingﬀects of the 7 Wm −2decrease in the SW. The changes
in cloud forcing occur mostly in the tropics.

Because we started from an RCP4.5 scenario in 2013, the initial atmosphere is not in radiative balance,

but is warming in response to anthropogenic greenhouse gases. The radiative imbalance at the top of the
model is 0.977 Wm −2in our CMIP5 run for years 2023–2038. Th ﬀeecet of increased clouds is to reduce
−2
this by a factor of 10 to 0.092 Wmbringingthemodelclosetotheradiativebalancethatwouldbeseen
in a steady state, such as the static conditions used for previous nuclear winter calculations. We ran an

additional case in which the 5Tg of BC is added in year 10 of the control run. These calculations conﬁrm
that our calculated BC mass, and surface anomalies in SW ﬂux, temperature, and precipitation are not
signiﬁcantlyﬀaected by any transient adjustments after the initial change in time step.

We also diagnosedﬀeects on stratospheric chemistry by comparing the ensemble average column ozone

from our control runs to the ensemble average from the CESM1(WACCM) CMIP5 runs for the ﬁrst 6years
after we introduced the change in time step. We found no signiﬁcﬀaenrtndies in either the global mean

or latitudinal distribution of column ozone due to the change in time stepﬀ.eTchs ef changing the
model time step are relatively minor compared to those of 5Tg of BC in the stratosphere, which is the

focus of our study.

3.Results

3.1. BC Rise and Meridional Transport

As in previous studies of this scenarRob[ock et a.l, 2007b;Mills et a.l, 2008], the BC aerosol absorbs
SW radiation, heating the ambient air, inducing a self-lofting that carries most of the BC well above the

tropopause. CESM1(WACCM) has 66 vertical layers and a model t∼ o1p5fkm, compared to 23 layers
up to∼80km for the GISS ModelE usedR boybock et a.l[2007b] and 39 layers up o80km for SOCOL3

used byStenke et a.l[2013].AsFigure1shows,wecalculatesigniﬁcantlyhigherloftingthan Robock et a.l
[2007b, compare to their Figure 1b], penetrating signiﬁcantly into the mesosphere, with peak mass mixing
ratios reaching the stratopause (50–60km) within 1month and persisting throughout the ﬁrst year.

This higher lofting, in conjunction witecets on the circulation we discuss later, produces signiﬁcantly
longer residence times for the BC than those in previous studies. At the end of 10years, our calculated

visible-band optical depths from the BC persist at 0.02–0.03, as shown in Figure 2. In contrast, Robock
et al.[2007b] calculate optical depths near 0.01 only at high latitudes after 10 years, a level that our

calculations do not reach for 15years.

3.2. BC Burden, Rainout, and Lifetime

During the ﬁrst 4months, 1.2–1.6 of the 5Tg of BC is lost in our 50nm experiment ensemble, and 1.6 Tg in
our 100nm experiment, mostly due to rainout in the ﬁrst few weeks as the plume initially rises through

the troposphere (Figure 3a). This is larger than the 1.0Tg initially lost in theuls otfa.l[2008],
which used a previous version of WACCM. This is likely due toﬀ ereenice in our initial distribution of
BC compared to that previous study, which injected 5Tg into a single column at a resolution four times

as coarse as ours. The more concentrated BC in the previous study likely produced faster heating and rise
into the stratosphere, mitigating rainout. Our calculated rainout contrasts with the lack of signiﬁcant rain-

out calculated by the GISS ModeR lEo[ ock et a.l, 2007b], which assumes that BC is initially hydrophobic
and becomes hydrophilic with a 24 efolding time scale. The mass burden reaching the stratosphere and

impacts on global climate and chemistry in our calculations would doubtless be greater had we made

9
Figure 1. The time evolution of BC mass mixing ratikg air) is shown for the average of the 50nm experiment ensemble.
The horizontal axis shows time in years since the emission of 5 Tg BC at 150–300 hPa on 1 January.

Figure 2. The time evolution of zonal mean total column BC optical depth in the visible part of the spectrum is shown for the 50nm
experiment ensemble average. The vertical axis showstiltaude. The horizontal average shows time in years.

asimilarassumptiontotheGISSModelE. Stenke et al.[2013]calculateaninitialrainoutof ∼2Tgintheir

interactive 5Tg simulations, which assumed BC radii of 50 and 100nm in two separate runs. After initial
rainout, the masse-folding time for our remaining BC is 8.7years for the average of our 50nm experiment

ensemble and 8.4years for our 100nm experiment, compared to the 6years reported Robyock et a.l
[2007b],∼6.5years byMills et al. [2008], 4–4.6years reported bS ytenke et al.[2013],and1yearforstrato-

spheric sulfate aerosol from typical volcanic eruptionOsm[ an et al., 2006]. Due to this longer lifetime,
after about 4.8years the global mass burden of BC we calculate in our ensemble is larger than that cal-

culated by the GISS ModelE, despite the initial 28% rainout loss. After 10 years, we calculate that 1.1Tg of
BC remains in the atmosphere in our 50nm experiment ensemble and 0.82Tg in our 100nm experiment,
compared to 0.54Tg calculated by the GISS ModelE and 0.07–0.14Tg calculated by SOCOL3.

The long lifetime that we calculate results from both the very high initial lofting of BC to altitudes, where
removal from the stratosphere is slow, and the subsequent slowing down of the stratospheric residual cir-
culation. The Brewer-Dobson circulation is driven waves whose propagation is ﬁltered by zonal winds,

Figure 3.The monthly global mean time evolution is shown for (a) the mass burden of black carbon (Tg), (b) the shortwave net ﬂux
anomaly at the surface (Wm (c) the surface temperature anomaly (K), and (d) the precipitation anomaly (mm/day). The dark blue
dashed line and light blue shading show the average and range of our 50nm experiment ensemble. The gold line shows our
simulation assuming a 100nm aerosol radius. The dark red dashed line and pink shading show the ensemble average and range for
Robock et a.l[2007a, 2007b] (data courtesy L. Oman). The grey and green lines show results from two 5 Tg BC simulaSttieonnksefrom

et al. [2013] (data courtesy A. Stenke), with assumed aerosol radii of 50 and 100 nm, respectively. Ensemble anomalies are calculated
with respect to the mean of the respective control simulation ensembles. Time 0 corresponds to the date of the BC injection (1
January in this study and 15 May in the other studies).

which are modulated by temperature gradieG narc[ia and Rand,e2l008].Asexplainedby Mills et a.l

[2008], the BC both heats the stratosphere and cools the surface, reducing the strength of the strato-
spheric overturning circulation. Figure 4 shows the vertical winds in the lower stratosphere, which bring

new air up from the troposphere and drive the poleward circulation, for the control and BC runs. The
middle-atmosphere heating and surface cooling reduce the average velocity of tropical updrafts by more
than 50%. Thisﬀ eect persists more than twice as long aM s ills et a.l[2008], which did not include any

ocean coolingﬀ eects.

3.3. Global Mean Climate Anomalies
The global climate anomalies shown in Figure 3 respond very similarly in our 50nm experiment ensemble

and our 100nm experiment; here we discuss the 50nm calculations. The 3.6Tg of BC that reaches the
middle atmosphere and spreads globally absorbs the incoming SW solar radiation, reducing the net SW
2
ﬂux at the surface b∼y12 W/m initially or about 8% (Figure 3b). This anomaly tracks the evolution of
the global mass burden of BC proportionally, similar to those calculated by GISS ModelE and SOCOL3.

The SW ﬂux in SOCOL3 seems to be more sensitive to BC than CESM1(WACCM), calculating comparable
initial ﬂux reductions with signiﬁcantly lower BC burdens. In contrast, GISS ModelE and CESM1(WACCM)

have similar sensitivity, producing very comparable ﬂux anomalies in years 4 and 5, when the global mass
burdens match most closely for the two models. After 10years, our calculated SW ﬂux anomaly persists at

Figure 4.The time evolution of the tropical lower stratospheric vertical wind (m∘/s) i∘ shown for (a) the control, (b) the 50nm
experiment, and (c) and the experiment minus the control. Values are ensemble aveuoe22s 22N. The horizontal
axis shows time in years. The left vertical axis shows pressure in hPa, and the right shows approximate pressure altitude in km.

−3.8 W/m,comparabletothemaximumforcingofthe1991MountPinatubovolcaniceruption[ Kirchner
et al., 1999]. This is 2.7 times that of the ﬂux anomaly calculated by GISS ModelE, with 2.0 times the mass

burden. SOCOL3 ﬂuxes have returned to normal after 10years as BC mass burdens become insigniﬁcant.
CESM1(WACCM) takes twice as long (20years) to do the same.

Our calculated global average surface temperatures dro∼ p1b.yK in the ﬁrst year (Figure 3c). This

response is initially slower than that calculated by the GISS ModelE, due to the large initial rainout, but
comparable to SOCOL3. The initial temperature anomalies for the three models correspond proportion-

ately to their initial SW anomalies. Our temperatures continue to decrease for 5years, however, reaching
amaximumcoolingof1.6Kinyear5,2–2.5yearsafterGISSModelEandSOCOL3beginwarmingfrom

their maximum cooling of comparable magnitude. After a decade, our calculated global average cooling
persists at∼1.1K, two to four times that calculated by GISS ModelE and SOCOL3. For CESM1(WACCM)

and GISS Model E, thisﬀ dirence is roughly proportional with the ratio of mass burdens calculated. Our
calculated cooling lags the recovery in mass burden and SW ﬂux, however. Global average temperatures
remain 0.25–0.50K below the control ensemble average in years 20–23, after SW ﬂuxes have returned

to the control range. The thermal inertia of the oceans, which have experienced more than a decade of
prolonged cooling, is responsible for much of this lag.

Precipitation rates drop globally∼b0y.18 mm/day within the ﬁrst year after the conﬂict. This 6% loss

in the global average persists for 5years, during which time our calculated response is not as strong
as that calculated by either GISS ModelE or SOCOL3. The fairly constant precipitation anomaly that we

calculate over the ﬁrst 5years is explained by the opposing trends in surface temperature and SW ﬂux
over this period, which tend to cancel each other out. In year 5, however, precipitation drops further as

temperatures continue to fall, reaching a maximum reduction of 9% in global precipitation while precip-
itation in the other two models is in their second year of recovery. At the end of a decade, our calculated
global precipitation is still reduced by 4.5%, and more than ﬁve times the reduction calculated at that time

by GISS ModelE or SOCOL3. After 26years, global average temperature and precipitation both remain
slightly below the control ensemble average.

3.4. Ocean and Sea Ice Response
As Figure 5 shows, sea ice extent expands signiﬁcantly over the ﬁrst 5years in the Arctic, and the ﬁrst

10years in the Antarctic. Sea ice extent is deﬁned as the total area of all surface grid points in the ocean
model with sea ice coverage greater

than 15%. Both hemispheres expe-
rience an earlier onset of sea ice for-

mation in the autumn, as revealed
by the seasonal maxima, consistent
withStenke et a.l[2013].IntheArc-

tic, sea ice extent increases peak at
10%–25% in years 4–7. Antarctic sea

ice extent peaks at 20%–75% larger
than the control ensemble in years

7–15,andremains5%–10%larger
throughout the years 20–26. These
vast expansions of sea iceﬀect not

only transfer of energy between the
atmosphere and the oceans but also

enhance planetary albedo, further
cooling the surface by reﬂecting more
Figure 5.Change in sea ice extent (%) for the 50nm experiment is shown
relative to the control. Sea ice extent is deﬁned as the area of all sea surface gridxpanding sea ice
points with ice fraction greater than 15%. The red line shows the ensembleo have large impacts on
average anomaly for the Southern Hemisphere. The blue line shows ocean life, strongly impacting the
the Northern Hemisphere. Shading around each line shows the range of the
experiment ensemble runs with respect to the control ensemble average. Theorganisms that are in equi-
horizontal axis shows time in years. The vertical axis shows relative change in iceurrent climate [e.g.,

extent area, 100%× (experiment−control)/control. Harley et a.l, 2006].

We also ﬁnd that the upper layer of the ocean experiences a prolonged cooling that penetrates to hun-
dreds of meters depth. Figure 6 shows the monthly global average ocean temperature anomalies at vari-

ous depths for the 50nm experiment ensemble, including ensemble variability, compared to the control
ensemble average. As the ﬁgure shows, average cooling exceeding 0.5K extends to 100m depth through

year 12. The upper 2.5m of the ocean has the same heat capacity per unit area as the whole depth of the
atmosphereG [ill,1982].Hence,thissigniﬁcantcoolingdownto100mdepthcreatesalong-livedther-
mal deﬁcit that maintains reduced surface temperature for decades. The temperature response takes

longer to penetrate to deeper waters, with temperatures at 1000 m continuing to drop for all 26 years
simulated.

3.5. Stratospheric Ozone Loss
The absorbing BC not only cools the surface but also severely heats the middle atmosphere (Figure 7). As

inMills et a.l[2008],wecalculateinitialglobalaveragetemperatureincreasesinexcessof80Knearthe
stratopause (50–60 km). AsR inobock et a.l[2007b],wecalculateglobalaveragestratosphericheatingin

excess of 30 K for the ﬁrst 5 years. Figure 7 also reveals the surface cooling discussed above, as well as a
cooling of the atmosphere above the BC layer, consistentRw obihck et a.l[2007b].

As inMills et a.l[2008],wecalculatemassiveozonelossasaconsequenceoftheseextremestratospheric

temperatures (Figure 8). Consistent with that work, we calculate a global average column ozone loss of
20%–25% persisting from the second through the ﬁfth year after the nuclear war, and recovering to 8%
column loss at the end of 10 years. Throughout the ﬁrst 5 years, column ozone is reduced by 30%–40% at

midlatitudes and by 50%–60% at northern high latitudes.

AsMills et a.l[2008] discussed, this
ozone loss results primarily from two

temperature-sensitive catalytic loss
cycles involving odd oxygen and odd

nitrogen, which accelerate at high
temperatures. In addition, analysis of

our current results shows that heat-
ing of the tropical tropopause allows

up to 4.3 times as much water vapor

to enter the lower stratosphere. The
enhanced water vapor has a twofold

eﬀect on depleting ozone. Photolysis of
water vapor produces both odd hydro-

gen and excited-state atomic oxygen,
O( 1D), depending on the wavelength of
1
dissociating sunlight. OD () is responsi-
ble for the production of odd nitrogen

Figure 6.The time evolution of the global average ocean temperaturen the stratosphere via reaction with
anomaly at various depths is shown. The lines show the monthly avera2e of theydrogen has its own cat-
experiment ensemble temperatures minus the monthly average of the control
alytic cycle destroying ozone. We calcu-
ensemble. Shading around each line shows the range of the experimelate that odd hydrogen in the tropical
ensemble runs with respect to the control ensemble average. The horizontal
axis shows time in years. The vertical axis shows temperature in K.ower stratosphere is enhanced by fac-
tors of 3–5.5 over the ﬁrst 2years after
1 1
the nuclear war. Similarly, O(D) is enhanced in the same region by factors of 4–7.6 D.)is( not the major
loss mechanism for N Ointhestratosphere,however,andN Olevelsareinitiallyslightlyelevatedinthe
2 2
tropical stratosphere, likely due to uplift by the initial rise of the plume, as describMellsbeyt a.l[2008].
Subsequent slowing of the stratospheric circulation produces reduced N Olevels,asincreasedageofair
2
results in increased chemical loss.

Ozone production rates are highest in the Tropics, where losses are dominated by transport of ozone to
higher latitudes. As air is transported poleward, the chemical losses accumulate, leading to higher col-

umn losses at higher latitudes. At southern high latitudes, ozone losses are mitigated by the elimination

Figure 7.The time evolution of the vertical proﬁle of global average temperature anomaly is shown. Values are for the 50nm

experiment ensemble average minus the control ensemble average. The horizontal axis shows time in years. The left vertical axis
shows pressure in hPa, and the right vertical axis shows approximate pressure altitude in km. Contours show temperature anomalies
in K.

Figure 8.The time evolution of the change (%) in zonal mean column ozone is shown. The change in the 50nm experiment
ensemble average is shown relative to the control ensembl10experiment−control)/control. The horizontal axis
shows time in years. The vertical axis shows latitude.

of the seasonal Antarctic ozone hole, which normally results from heterogeneous chemistry occurring on
polar stratospheric clouds (PSCs) only at the extreme low temperatures present in the Antarctic strato-

sphere. We do not includeﬀe ects of heterogeneous chemistry on BC aerosol, which is less understood
than chemistry on sulfates and PSCs.

3.6. Changes in Surface UV Radiation
We used the TUV (tropospheric ultraviolet-visible) m Maodreoln[ich and Floe997]tocalculatethe

impacts of this massive ozone loss on ﬂuxes of damaging UV radiation reaching the Earth’s surface. TUV
simulates the attenuation of sunlight on its journey through Earth’s atmosphere. The model has been
used to study a wide range of topics including chemistry of the rem Woateg[a et a.l, 1992] and urban

atmosphereC [astro et a.l, 2001], chemistry within snowpacFsis[her et a.,l2005], incidence of skin cancer
[Thomas et a.l, 2007], methane emissions from planBtslo[om et a.l, 2010], and potential changes to UV

resulting from asteroid impacP tsie[razzo et a.,l2010] and geoengineerTil[mes et a.l, 2012]. The method
used in this study is based on that describedLeey-Taylor et a.[l2010].

We used TUV to calculate UV ﬂuxes for clear sky conditions, based on the monthly average column ozone

and absorbing BC distributions calculated for the control and experiment ensemble averages of our
CESM1(WACCM) runs. To reduce computational overhead, we precalculated lookup tables of UV variation
with respect to ozone, solar zenith ang▯l), (and surface elevation, using the full 80km atmospheric

column considered by TUV. We then constructed global distributions of UV from the modeled WACCM
ozone distributions using Beer’s law to account for the slant-path absorption by the stratospheric BC,

performing the calculation daily to account for vary▯iWgeexpressthemonthlyaveragedUVresultsin
terms of the international UV Index (UVI) [WHO, WMO, UNEP, and ICNIRP, 2002], which weights noontime
UV ﬂuxes by an “action spectrum” to account for the wavelength dependence o ﬀfetiveness of solar

radiation at causing skin damagM ec[Kinlay and Dﬀiey,1987].

Figure 9 shows UVI in the peak summer months of June for the Northern Hemisphere and December for
the Southern Hemisphere. The World Health Organization recommends that sun protection measures be

taken for UV indices of 3 and above, and characterizes UVI values of 8–10 as “very high,” warranting extra
protection measures to avoid exposure to sunlight during midday hours. UVI greater than 11 is consid-

ered “extreme.” We calculate UVI increases of 3–6 throughout the midlatitudes in summer, bringing peak
values oﬀthe charts at 12–21 over the most populous regions of North America and southern Europe in
June. We ﬁnd similar increases for Australia, New Zealand, southern Africa, and South America in Decem-

ber. Skin damage varies with skin type, with burn times inversely proportional to UVI. Hence, a moderately
fair-skinned North American who experiences a painful, noticeable sunburn after 10min in the sun at

noon in June for a UVI of 10 would receive an equivalent level of damage after 6.25min for a UVI of 16.

Figure 9.UV index in June (left) and December (right) is shown for the control (a, b), the experiment (c, d), and the experiment
minus the control (e, f). Values are ensemble averages for year 3.

Stenke et a.l[2013]calculatesimilarlydramaticincreasesinUVradiationduetoozoneloss.Theyalso

report that the attenuation of solar ﬂuxes from BC absorption was signiﬁcant enough in high-latitude
winter to reduce UV levels by 30% when they are most needed for vitamin D production. In contrast, we

do not ﬁnd that BC attenuation is signiﬁcant enoughﬀ tseot the UV increases from ozone loss.

The calculations shown in Figure 9 include absorption of UV by the BC, but not scattering, which presents
an additional source of uncertainty. We performed a sensitivity test at 305 nm using a nominal single-
scattering albedo of 0.31 for a 1 km depth soot layer centered on 27 km and a total ozone column of

200 DU. We calculate that BC scattering produces small reductions in ground-level UV irradiance, rang-
ing from 4% for overhead sun and soot optical depth of 0.05 to 12% ▯ fofr88 and soot optical depth
of 0.1. Hence, scattering would only marginallﬀyset the 30%–100% increases in UV irradiance that we

calculate for summer in the extratropics.

3.7. Eﬀects on Vegetation and Agriculture

The severe increases in UV radiation following a regional nuclear war would occur in conjunction with the
coldest average surface temperatures in the last 1000 yeM arsn[n et a.l, 1999]. Although global average
surface temperatures would drop by 1.5 K (Figure 3c), broad, populated regions of continental landmasses

would experience signiﬁcantly larger cooling, as shown in Figure 10. Winters (JJA) in southern Africa and
South America would be up to 2.5 K cooler on average for 5 years, compared to the same years (2–6) in

the control run. Most of North America, Asia, Europe, and the Middle East would experience winters (DJF)
that are 2.5–6 K cooler than the control ensemble, and summers (JJA) 1–4 K cooler.

Similarly, the 6% global average drop in precipitation that persists through years 2–6 (Figure 3d) trans-
lates into more signiﬁcant regional drying (Figure 11). The most evident feature is over the Asian monsoon

region, including the Middle East, the Indian subcontinent, and Southeast Asia. Broad precipitation reduc-
tions of 0.5–1.5 mm/day would reduce annual rainfall by 20%–80%. Similarly, large relative reductions in
rainfall would occur in the Amazon region of South America, and southern Africa. The American South-

west and Western Australia would be 20%–60% dRrioebr.ock et a.l[2007b] predict a broadly wetter Sahel
region as a result of a weaker Hadley circulatiSon. ke et a.l[2013] do not ﬁnd such increased precipita-
tion, and nor do we, despite some increase in precipitation near Morocco.

FollowingRobock et a.l[2007b],wehavecalculatedthechangeinthefrost-freegrowingseason,deﬁned
∘
as the number of consecutive days in a 1year period with minimum temperatures abC ovei0ure 12).

Figure 10.Change in surface temperature (K) for (a) June to August and (b) December to February. Values are 5year seasonal
ensemble averages for years 2–6, experiment minus control.

Because our globally averaged surface temperatures continue to cool until year 6, we show the average

change in the growing season over years 2–6. The length of the average growing season is reduced by up
to 40 days throughout the world’s agricultural zones over these 5 years. This is similar to the results that
Robock et a.l[2007b]reportfortheirﬁrstyear,withsigniﬁcantregionaldiﬀerences. We ﬁnd more signif-

icant decreases in Russia, North Africa, the Middle East, and the Himalayas than the previous study, and
somewhat smallerﬀ eects in the American Midwest and South America.

The land component in CESM1(WACCM) is CLM4CN, a comprehensive land carbon cycleL mawdrel[e

et al., 2011]. CLM4CN is prognostic with respect to carbon and nitrogen state variables in vegetation, litter,
and soil organic matter. Vegetation carbonﬀisected by temperature, precipitation, solar radiation (and
its partitioning into direct anduise radiation), humidity, soil moisture, and nitrogen availability, among

other factors. We calculate an average loss of 11 Pg C from vegetation (2% of the total), which equates
to an increase in atmospheric C2of about 5 ppmv (5×10 molec/molec air). We also note a signiﬁcant

(42%–46%) increase in C loss from ﬁres in the Amazon over the ﬁrst 8 years in two of our three 50nm
experiment ensemble. The third run showed Amazon ﬁre loss 13% higher than the control average, but
within the variability of the control ensemble. Our runs do not account for the atmospﬀeritcseof CO
2
or smoke emissions from the land component, but the smoke from the Amazon-kindled ﬁres would be a
positive feedback that would enhance the cooling we have found.

4.Discussion

Pierazzo et a.l[2010]reviewedliteratureconsideringtheeﬀects of large and prolonged increases in

UV-B radiation, similar to those we calculate, on living organisms, including agriculture and marine

Figure 11.Changes in (a) absolute (mm/day) and (b) relative (%) surface precipitation. Values are 5year seasonal ensemble averages
for June to August, years 2–6, experiment minus control.

Figure 12.Change in frost-free growing season in days for (a) January to December in the Northern Hemisphere and (b) July to June
in the Southern Hemisphere. Values are 5year seasonal ensemble averages for years 2–6, experiment minus control.

ecosystems. Generalﬀeects on terrestrial plants have been found to include reduced height, shoot mass,

and foliage areaC[aldwell et a.l, 2007].Walbot[1999] found the DNA damage to maize crops from 33%
ozone depletion to accumulate proportionally to exposure time, being passed to successive generations,
and destabilizing genetic lines. Research indicates that UV-B exposure may alter the susceptibility of

plants to attack by insects, alter nutrient cycling in soils (including nitrogen ﬁxation by cyanobacteria),
and shift competitive balances among specC iea[well et a.l, 1998;Solheim et a.l, 2002;Mpoloka,2008].

The ozone depletion we calculate could also damage aquatic ecosystems, which supply more than 30%

of the animal protein consumed by humaH ns.der et a.l[1995]estimatethat16%ozonedepletioncould
reduce phytoplankton, the basis of the marine food chain, by 5%, resulting in a loss of 7 million tons of

ﬁsh harvest per year. They also report that elevated UV levels damage the early developmental stages of
ﬁsh, shrimp, crab, amphibians, and other animals. The combin ﬀects of elevated UV levels alone on

terrestrial agriculture and marine ecosystems could put signiﬁcant pressures on global food security.

The ozone loss would persist for a decade at the same time that growing seasons would be reduced by

killing frosts, and regional precipitation patterns would shift. The combination of years of killing frosts,
reductions in needed precipitation, and prolonged enhancement of UV radiation, in addition to impacts

on ﬁsheries because of temperature and salinity changes, could exert signiﬁcant pressures on food sup-
plies across many regions of the globe. As the January to May 2008 global rice crisis demonstrated, even

relatively small food price pressures can be ampliﬁed by political reactions, such as the fearful restrictions
on food exports implemented by India and Vietnam, followed by Egypt, Pakistan, and Brazil, which pro-

duced severe shortages in the Philippines, Africa, and Latin America [Slayton, 2009]. It is conceivable that
the global pressures on food supplies from a regional nuclear conﬂict could, directly or via ensuing panic,

signiﬁcantly degrade global food security or even produce a global nuclear famine.

5.Summary

We present the ﬁrst simulations of the chemistry-clﬀ iecattseoef smoke produced by a nuclear war

using an Earth system model that includes both stratospheric chemistry and feedbacks on sea ice
and deep ocean circulation. We calculate impacts on surface climate persisting signiﬁcantly longer

than previous studies, as a result of several feedback mechanisms. First, BC absorbs sunlight, heating
ambient air, and self-lofts to the upper stratosphere, a region treated with greater vertical resolution

in CESM1(WACCM) than in the model usedRb oybock et a.l[2007b]. Second, the BC spreads globally,
absorbing sunlight, which heats the stratosphere and cools the surface. This haﬀsetchteoe f reducing

the strength of the stratospheric circulation and increasing the lifetime of BC in the stratosphere. Third,

the reduction of surface temperatures cools the upper 100 m of the oce> an.byK for 12 years, and
expands ice extent on sea and land. This lends inertia to the surface cooling due to both thermal mass

and enhanced albedo, causing recovery in surface temperatures to lag the recovery in BC by a decade or
more. As a result, we calculate that surface temperatures remain below the control ensemble range even

26 years after the nuclear war.

Acknowledgments The global average temperature increase in the stratosphere following the BC injection initially exceeds
We thank Luke Oman and Andrea 70 K, and persists above 30 K for 5 years, with full recovery taking two decades. As in previous studies, this
Stenke for providing us with data
from their simulations. We thank temperature increase produces global ozone loss on a scale never observed, as a result of several chemical
Jean-François Lamarque, Ryan Neelymechanisms. The resulting enhancements to UV radiation at the surface would be directly damaging to
Charles Bardeen, Andrew Gettel-
human health, and would damage agricultural crops, as well as ecosystems on land and in the oceans.
man, Anja Schmidt, an anonymous
reviewer, and associate editor forThese results illustrate some of the severe negative consequences of the use of only 100 of the smallest
their constructive input on this work.
Simulations conducted for this workuclear weapons in modern megacities. Yet the United States, Russia, the United Kingdom, China, and
were conducted at NASA High End France each have stockpiles of much larger nuclear weapons that dwarf the 100 examRio nbedckere [
Computing Capability’s Pleiades clus-
et al., 2007a;Toon et a.,l2007]. Knowing the perils to human society and other forms of life on Earth of
ter, with computing time supportedeven small numbers of nuclear weapons, societies can better understand the urgent need to eliminate
by NASA grant NNX09AK71G. Alan
Robock is supported by NSF grant this danger worldwide.
AGS-1157525. The National Center for
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THE MAP SERIED EMONSTRATING THGLOBAL SPREAD OSMOKE FROM A

REGIONALN UCLEARFALLOUTB ETWEENINDIA ANPAKISTAN,ANDSELECTED
M APS FROM TH2014REPORTSUBMITTED AA NNEX1Figures 1-3 demonstrate the global spread of black carbon (“BC”) as a result of India

and Pakistan detonating 50 15Kiloton (“kt”) nuclear weapons on May 14. They are
taken from the website of Alan Robock of Rutgers University

(http://climate.envsci.rutgers.edu/nuclear/BCabsoptdaily.gif )
Figures 4 and 5 demonstrate the change in surface air temperature and frost-free
growing seasons following an almost identical scenario – the exchange takes place on
st
January 1 2013. These figures are taken from the report submitted as Annex 1.

Figure 1

Figure 2 shows 5Tg of smoke rising into the atmosphere as a result of India and

Pakistan detonating 15kt of nuclear weapons the day before.

Shown here is 5 teragrams of smoke (BC) rising into the atmosphere as a result of
th
India and Pakistan detonating 50 15kt of nuclear weapons beginning 14 May.
http://climate.envsci.rutgers.edu/nuclear/BCabsoptdaily.gif accessed on 11 December

2014 at 12.38pm.Figure 2

Shown here is the dramatic rise of BC into the atmosphere and it’s spreading
globally. You can see that within 10 days of the fallout the Marshall Islands will be
experiencing the detrimental effects of thick smoke in the atmosphere.
http://climate.envsci.rutgers.edu/nuclear/BCabsoptdaily.gif accessed on 11 December

2014 at 12.38pm.Figure 3

Figure 3 you can see that in two months the effect is global.

Here it is shown that after two months the BC has spread globally.

http://climate.envsci.rutgers.edu/nuclear/BCabsoptdaily.gif accessed on 11 December
2014 at 12.38pm. Figure 4
Earth’sFuture 10.1002/2013EF000205
Change in Surface Air Temperature

Figure 1.hange in surface temperature (K) for (a) June to August and (b) December to February. Values are 5year seasonal
ensemble averages for years 2–6, experiment minus control.
Shown here is the change in surface air temperature for June-August in the top map,

and December-February in the bottom. The Marshall Islands will face cooling
towBecause our globally averaged surface temperatures continue to cool until year 6, we show the average
accessed 11 December 2014 at 12.40pm.
change in the growing season over years 2–6. The length of the average growing season is reduced by up
to 40 days throughout the world’s agricultural zones over these 5 years. This is similar to the results that
Robock et.[l07b]reportfortheirﬁrstyear,withsigniﬁcantregionﬀerences. We ﬁnd more signif-

icant decreases in Russia, North Africa, the Middle East, and the Himalayas than the previous study, and
somewhat smalle ﬀrcets in the American Midwest and South America.

The land component in CESM1(WACCM) is CLM4CN, a comprehensive land carLb awnrcycle model [

et a.l, 2011]. CLM4CN is prognostic with respect to carbon and nitrogen state variables in vegetation, litter,
and soil organic matter. Vegetation cﬀbectes by temperature, precipitation, solar radiation (and

its partitioning into direﬀudsedriadiation), humidity, soil moisture, and nitrogen availability, among
other factors. We calculate an average loss of 11 Pg C from vegetation (2% of the total), which equates
to an increase in atmospheric CObout 5 ppmv ×(50 molec/molec air). We also note a signiﬁcant
2
(42%–46%) increase in C loss from ﬁres in the Amazon over the ﬁrst 8 years in two of our three 50nm
experiment ensemble. The third run showed Amazon ﬁre loss 13% higher than the control average, but

within the variability of the control ensemble. Our runs do not account forﬀeatmoofp2heric e
or smoke emissions from the land component, but the smoke from the Amazon-kindled ﬁres would be a FigFigure 5ges in (a) absolute (mm/day) and (b) relative (%) surface precipitation. Values are 5year seasonal ensemble averages
for June to AugusChange in Frost-Free Growing Season Days

FigureCh.ange in frost-free growing season in days for (a) January to December in the Northern Hemisphere and (b) July to June
in the Southern Hemisphere. Values are 5year seasonal ensemble averages for years 2–6, experiment minus control.

Shown here is the change in frost-free growing season days for January-December in
the Northern Hemisphere in the top map, and July-June in the Southern Hemisphere
ecoin the bottom map. From this it can be determined that the United States, where thehoot mass,
and foliageCarlaw[el,20l0W]albot999] found the DNA damage to maize crops from 33%%
shorter growing season.
ozoat 12.40pm.n to accumulate proportionally to exposure time, being passed to successive generations,
and destabilizing genetic lines. Research indicates that UV-B exposure may alter the susceptibility of
plants to attack by insects, alter nutrient cycling in soils (including nitrogen ﬁxation by cyanobacteria),

and shift competitive balancesCaaldwngl.,199e8;heim.e,20l02;pol,0

INDIASL ETTER TO THC OURTD ATED6JUNE 2014Annex 4 ANNEX4

THE REPUBLIC OFNDIA’SLETTER TO THECOURT 10JUNE 2014 ANNEX5

THE REPUBLIC OFINDI’SA RTICLE36PARA.2D ECLARATION ANNEX6

THE REPUBLIC OF TMEARSHALLSLANDSARTICLE36PARA.2DECLARATION Reference: C.N.261.2013.TREATIES-I.4 (Depositary Notification)

DECLARATIONS RECOGNIZING AS COMPULSORY THE JURISDICTION OF

THE INTERNATIONAL COURT OF JUSTICE UNDER ARTICLE 36,
PARAGRAPH 2, OF THE STATUTE OF THE COURT

M ARSHALL SLANDS : DECLARATION UNDER ARTICLE 36 (2)OF THE STATUTE

The Secretary-General of the United Nations, acting in his capacity as depositary,
communicates the following:

The above action was effected on 24 April 2013.

In accordance with paragraph 4 of article 36 of the Statute of the International Court of Justice,
… the authentic English text of the declaration and the French translation are transmitted herewith.

30 April 2013

Attention: Treaty Services of Ministries of Foreign Affairs and of international organizations concerned.
Depositarynotifications are issuedinelectronicformatonly. Depositarynotificationsaremadeavailableto

the Permanent Missions to the United Nations in the United Nations Treaty Collection on the Internet at
http://treaties.un.org, under"DepositaryNotifications(CNs)". Inaddition,thePermanentMissions,aswell
asotherinterestedindividuals,cansubscribetoreceivedepositarynotificationsbye-mailthroughtheTreaty
Section's "Automated Subscription Services", which is also available at http://treaties.un.org. h t f o f l a h e b n o e r a l c

5 1 s i h t s d n a l s I l l a h s r a M e h t f o c i

m u r B e d . A y n o
d n a t n e d i s e r P e h t o t
” s r i a f f A n g

Document Long Title

Annexes