Four degrees and beyond: the potential for a global ... - Amper

More documents

Recommendations

Info

226 R. Warren just beginning. Hence, climate change impacts on ecosystems may threaten our future ability to protect human health, especially as pathogens evolve resistance to current treatments. Disturbance to forests in proximity to human habitation can lead to increased prevalence of disease. For example, Olson et al. [35] identified a 48 per cent increase in malaria incidence associated with a loss of 4.3 per cent of forest cover ina3yearperiod. This can be via a reduction in populations of the disease vector’s predators, or because of changing environmental conditions allowing them to outcompete benign related species [36]. Modelling these interactions into the future needs to be a priority for future research. A significant proportion of the world’s population is entirely dependent on fish. Cheung et al. [37] report on dramatic turnovers in fish assemblages for climate changes well below 4 ◦ C, particularly in the Arctic and Antarctic, potentially disrupting ecosystem functioning and numerous local extinctions in the subpolar regions, the tropics and semi-enclosed seas. Communities particularly at risk from changing fisheries resources are on small reef islands on the rim of atolls such as the Maldives [25]. Important linkages between climate change impacts on ecosystems and those upon agricultural and other systems are generally omitted from impacts assessments. For example, as bioclimatic envelopes of pest and disease vectors change, new pests and diseases may invade systems, requiring new diseaseresistant crop varieties to maintain agricultural productivity [38]. Wild crop genotypes are an important resource yet climate change impacts upon these have only recently been considered [31]. However, quantifying potential risks to food production owing to loss of wild crop genotypes is not currently feasible. Several recent studies consider crop damage owing to pests in future decades [21] and highlight the importance of interactions between CO2 concentrations and temperature, and precipitation in determining the size of these effects. It would be useful and feasible to explore ways to combine such projections with global agricultural models of climate change impacts on crops, which typically omit impacts of pests. While many of the world’s staple crops reproduce vegetatively, or via wind pollination, many others rely on pollinators. Over 80 per cent of the 264 crops grown in the EU depend on insect pollination [38]. However, few pollinator distributions have been modelled in relation to climate change. Quantifying potential risks is difficult because limited information exists on the relationship between crops, their pollinators and climate change. It is recommended to collect such information and carry out bioclimatic or ecophysiological modelling of species, or species groups, identified as the key pollinators in relation to their crops. Much more severe and more difficult to model are the potential interactions between wild species and pollinators. (b) Interactions mediated by human adaptation to climate change A key interaction omitted from modelling approaches is that between impacts in one sector and adaptation by humans to impacts in another sector. For example, there are potential consequences to health and ecosystem sectors resulting from human adaptation in agricultural, hydrological and coastal sectors. Phil. Trans. R. Soc. A (2011) Downloaded from rsta.royalsocietypublishing.org on November 30, 2010
Review. Interactions in a 4 ◦ C world 227 Human adaptation to climate change-induced water stress can include anything from local collection of rainwater on buildings through the building of dams to unsustainable increases in groundwater abstraction. Dam construction can damage wetlands, inundate forests and may encourage reproduction of disease agents by concentrating them in lakes close to human habitation, as has occurred in Burkina Faso, Sudan and Egypt for schistosomiasis and malaria [36]. Even for small amounts of climate change it will become infeasible to continue to grow presently used crop varieties in tropical or desert areas where crops are already grown close to their thermal limits. By 4 ◦ C, crops in many regions are projected to be affected and adaptation over potentially large parts of the globe may be needed (table 3). This could include switching to new crop types, installing irrigation systems, agricultural intensification, shifting agricultural lands to new areas and/or the use of genetically modified crops resistant to future climates [1,4,17,20]. Changes to irrigation practices may exacerbate water stress and may reduce water supplies to wetlands, which themselves provide key ecosystem services. Agricultural intensification can have negative impacts, including increases in nutrient run-off into rivers and estuaries, where it may cause local anoxia and contribute to greenhouse gas emissions of N2O [12]. The wholesale shifting of agricultural lands has profound implications, as discussed below. Human adaptation responses to sea-level rise range from managed retreat, building of dykes and construction of flood barriers [26]. It is widely reported to be cost-effective to protect major cities against a sea-level rise of up to 2 m, but this, as the authors acknowledge, is only a partial analysis. The coastal protection considered only safeguards cities and does not protect coastal infrastructure away from cities, which may be extensive, nor does it avoid large-scale loss of coastal wetlands, mangroves and saltmarshes. Building of dykes to protect towns may be to the detriment of associated natural ecosystems [39], such as mangroves and saltmarshes where many marine fish species spawn. Such ecosystems also protect coastlines against storm surge and tsunamis [40]. Hence, cost-effectiveness analyses for coastal protection need to include losses of these ecosystems and the consequences for fisheries and coastal infrastructure. This volume contains some of the few studies of climate change impacts considering climate change as great as 4 ◦ C. Table 3 collates some of the estimates appearing in this volume and elsewhere and compares them with estimates of impacts at 2 ◦ C. Several of these estimates are taken from the AVOID project [27]. Considering the large impacts in the agricultural, hydrological and ecosystem sectors expected in a 4 ◦ C world, future use of land and water would need to be carefully planned, taking into account the needs of humans, agriculture and ecosystems and their services. In this context, limits (physical or financial) to simultaneous adaptation in multiple sectors need to be considered. The global cost of adapting to climate change from 2010 to 2050 (2 ◦ C) has been estimated to be $75–100 billion each year [41]. In the agricultural sector, Easterling et al. [21] estimated that climate change damages to wheat, rice and maize could be avoided by adaptation up to a limit of a temperature increase of 1.5–3 ◦ C in tropical regions and 4.5–5 ◦ C in temperate regions. Temperature changes of between 4 and 8 ◦ C are projected in the summer across various temperate and tropical regions for a global 4 ◦ C temperature rise [42]. This suggests that these adaptive capacities might be Phil. Trans. R. Soc. A (2011) Downloaded from rsta.royalsocietypublishing.org on November 30, 2010
Page 1 and 2:
ISSN 1364-503X volume 369 number 19
Page 3 and 4:
Phil. Trans. R. Soc. A (2011) 369,
Page 5 and 6:
Editorial David Garner Phil. Trans.
Page 7 and 8:
Four degrees and beyond: the potent
Page 9 and 10:
Preface 5 commitments might give us
Page 11 and 12:
Downloaded from rsta.royalsocietypu
Page 13 and 14:
8 M. New et al. In the final plenar
Page 15 and 16:
10 M. New et al. supports the messa
Page 17 and 18:
12 M. New et al. Table 1. Impacts a
Page 19 and 20:
14 M. New et al. actors (NNSAs)—r
Page 21 and 22:
16 M. New et al. as permanent crop
Page 23 and 24:
18 M. New et al. 24 Boe, J. L., Hal
Page 25 and 26:
Beyond 'dangerous' climate change:
Page 27 and 28:
Beyond dangerous climate change 21
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
(i) Energy and industrial process e
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
(a) 50 (b) GtCO 2e yr -1 40 30 20 1
Page 41 and 42:
Table 1. Summary of scenario pathwa
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Cumulative carbon emissions, emissi
Page 53 and 54:
46 N. H. A. Bowerman et al. althoug
Page 55 and 56:
48 N. H. A. Bowerman et al. a likel
Page 57 and 58:
50 N. H. A. Bowerman et al. (b) Mod
Page 59 and 60:
52 N. H. A. Bowerman et al. In most
Page 61 and 62:
54 N. H. A. Bowerman et al. rates o
Page 63 and 64:
56 N. H. A. Bowerman et al. (a) pea
Page 65 and 66:
58 N. H. A. Bowerman et al. We can
Page 67 and 68:
60 N. H. A. Bowerman et al. (a) rel
Page 69 and 70:
62 N. H. A. Bowerman et al. (a) 0.3
Page 71 and 72:
64 N. H. A. Bowerman et al. 4. Conc
Page 73 and 74:
66 N. H. A. Bowerman et al. increas
Page 75 and 76:
Page 77 and 78:
emissions (GtC) Review. Global warm
Page 79 and 80:
Review. Global warming reaching 4
Page 81 and 82:
Page 83 and 84:
global surface warming (°C) 6 5 4
Page 85 and 86:
Page 87 and 88:
temperature (relative to 1861-1890
Page 89 and 90:
°C above pre-industrial 8 7 6 5 4
Page 91 and 92:
Page 93 and 94:
Regional temperature and precipitat
Page 95 and 96:
86 M. G. Sanderson et al. technical
Page 97 and 98:
88 M. G. Sanderson et al. Table 1.
Page 99 and 100:
90 M. G. Sanderson et al. (a) 90°
Page 101 and 102:
92 M. G. Sanderson et al. An area o
Page 103 and 104:
94 M. G. Sanderson et al. South Ame
Page 105 and 106:
96 M. G. Sanderson et al. For DJF (
Page 107 and 108:
98 M. G. Sanderson et al. 12 Betts,
Page 109 and 110:
Page 111 and 112:
Water availability in +2 ◦ C and
Page 113 and 114:
(ii) Water stress index Water avail
Page 115 and 116:
(b) (c) (d) (a) Water availability
Page 117 and 118:
Page 119 and 120:
(a) number of models, black line nu
Page 121 and 122:
change in run-off (%) change in run
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Agriculture and food systems in sub
Page 129 and 130:
118 P. K. Thornton et al. 1. Introd
Page 131 and 132:
120 P. K. Thornton et al. increases
Page 133 and 134:
122 P. K. Thornton et al. Table 1.
Page 135 and 136:
124 P. K. Thornton et al. century.
Page 137 and 138:
126 P. K. Thornton et al. and polit
Page 139 and 140:
128 P. K. Thornton et al. — The r
Page 141 and 142:
130 P. K. Thornton et al. keepers i
Page 143 and 144:
132 P. K. Thornton et al. 3 Frayne,
Page 145 and 146:
134 P. K. Thornton et al. 41 Erikse
Page 147 and 148:
136 P. K. Thornton et al. 83 Challi
Page 149 and 150:
Page 151 and 152:
Humid tropical forests on a warmer
Page 153 and 154:
(a) Humid tropical forests on a war
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
0 retraction risk 17 120 80 40 (a)
Page 163 and 164:
Page 165 and 166:
0 retraction risk 17 120 80 40 0
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Sea-level rise and its possible imp
Page 175 and 176:
162 R. J. Nicholls et al. expected.
Page 177 and 178:
164 R. J. Nicholls et al. sea-level
Page 179 and 180:
166 R. J. Nicholls et al. mean temp
Page 181 and 182:
168 R. J. Nicholls et al. interglac
Page 183 and 184:
170 R. J. Nicholls et al. discussed
Page 185 and 186:
172 R. J. Nicholls et al. land loss
Page 187 and 188:
174 R. J. Nicholls et al. global ad
Page 189 and 190:
176 R. J. Nicholls et al. Hence, th
Page 191 and 192: 178 R. J. Nicholls et al. to climat
Page 193 and 194: 180 R. J. Nicholls et al. 43 Pardae
Page 195 and 196: Climate-induced population displace
Page 211 and 212: Downloaded from rsta.royalsocietypu
Page 213 and 214: 198 M. Stafford Smith et al. the di
Page 215 and 216: 200 M. Stafford Smith et al. greate
Page 217 and 218: 202 M. Stafford Smith et al. Table
Page 219 and 220: 204 M. Stafford Smith et al. (c) Go
Page 221 and 222: 206 M. Stafford Smith et al. mean g
Page 223 and 224: 208 M. Stafford Smith et al. These
Page 225 and 226: 210 M. Stafford Smith et al. consid
Page 227 and 228: 212 M. Stafford Smith et al. — De
Page 229 and 230: 214 M. Stafford Smith et al. 12 Lem
Page 231 and 232: 216 M. Stafford Smith et al. 51 Ste
Page 233 and 234: REVIEW Phil. Trans. R. Soc. A (2011
Page 235 and 236: Review. Interactions in a 4 ◦ C w
Page 239 and 240: spread in mosquitoborne disease may
Page 241: [89,94,95] further acidification by
Page 259: Editorial Editorial 3 D. Garner Pre
show all

Four degrees and beyond: the potential for a global ... - Amper

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?