THE WORKING GROUP II CONTRIBUTION TO THE IPCC'S FIFTH ASSESSMENT REPORT. J.A. Marengo LA SPM W2 CLA Chapter 27 WG2, CCST INPE

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1 THE WORKING GROUP II CONTRIBUTION TO THE IPCC'S FIFTH ASSESSMENT REPORT J.A. Marengo LA SPM W2 CLA Chapter 27 WG2, CCST INPE

2 CLIMATE CHANGE 2014: IMPACTS, ADAPTATION, AND VULNERABILITY

3 KEY MESSAGES Climate change is already causing harm. The more we warm the climate the more risks we will face including the possibility of irreversible damage. Effective and inclusive climate-change adaptation can help build a richer more resilient world n the near-term and beyond.

4 Climate change: Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions, and persistent anthropogenic changes in the composition of the atmosphere or in land use. Hazard: The potential occurrence of a natural or human-induced physical event or trend or physical impact that may cause loss of life, injury, or other health impacts, as well as damage and loss to property, infrastructure, livelihoods, service provision, ecosystems, and environmental resources. Hazard usually refers to climate-related physical events or trends or their physical impacts. Exposure: The presence of people, livelihoods, species or ecosystems, environmental functions, services, and resources, infrastructure, or economic, social, or cultural assets in places and settings that could be adversely affected. Vulnerability: The propensity or predisposition to be adversely affected. Vulnerability encompasses a variety of concepts and elements including sensitivity or susceptibility to harm and lack of capacity to cope and adapt.

5 Impacts: Effects on natural and human systems. In this report, the term impacts is used primarily to refer to the effects on natural and human systems of extreme weather and climate events and of climate change. Impacts generally refer to effects on lives, livelihoods, health, ecosystems, economies, societies, cultures, services, and infrastructure Risk: The potential for consequences where something of value is at stake and where the outcome is uncertain, recognizing the diversity of values. Risk is often represented as probability of occurrence of hazardous events or trends multiplied by the impacts if these events or trends occur. Adaptation: The process of adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to moderate or avoid harm or exploit beneficial opportunities. In some natural systems, human intervention may facilitate adjustment to expected climate and its effects. Resilience: The capacity of social, economic, and environmental systems to cope with a hazardous event or trend or disturbance, responding or reorganizing in ways that maintain their essential function, identity, and structure, while also maintaining the capacity for adaptation, learning, and transformation.

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7 IMPACTS CLIMATE Natural Variability Vulnerability SOCIOECONOMIC PROCESSES Socioeconomic Pathways Anthropogenic Climate Change Hazards RISK Adaptation and Mitigation Actions Exposure Governance EMISSIONS and Land-use Change

8 WIDESPREAD OBSERVED IMPACTS A CHANGING WORLD

9 Global patterns of impacts in recent decades attributed to climate change, based on studies since the AR4. Impacts are shown at a range of geographic scales.

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11 Impactos atribuídos às mudanças climáticas e relatados na literatura científica (alta confiança) África - Derretimento das geleiras no topo das montanhas do leste da África - Aumento da temperatura da superfície do Lago Kariba - Declínio de recifes de corais africanos América do Norte - Redução das geleiras no norte do continente - Diminuição da disponibilidade de água durante a primavera - Mudanças no padrão de neve no oeste do continente - Espécies de peixes do Atlântico migrando para o norte em busca de águas mais frias - Mudanças na distribuição de mexilhões na costa oeste dos EUA - Mudanças no padrão de migração dos salmões América Latina - Redução das geleiras dos Andes - Aumento do fluxo dos rios da Bacia da Prata Ásia - Degradação do permafrost da Sibéria - Aumento da força da corrente de quatro rios que recebem água das geleiras do Himalaia - Avanço de arbustos na tundra siberiana - Declínio dos recifes de corais asiáticos - do Ártico

12 Europa - Recuo das geleiras dos Alpes, da Escandinávia e da Islândia - Surgimento de flores e plantas mais cedo do que o comum, antes da primavera - Aumento da área de florestas suscetíveis a incêndios em Portugal e Grécia - Migração de peixes e aves marinhas para o Atlântico Norte, em busca de águas mais frias Oceania - Diminuição das correntes dos rios no sudoeste australiano - Mudanças na distribuição genética de pássaros, borboletas e plantas na Austrália - Aumento de casos de braqueamento na Grande Barreira de Corais da Austrália Polos - Redução do mar congelado no Ártico no verão - Redução no volume de gelo das geleiras do Ártico - Impacto nos animais das regiões de neve e tundra no Polo Norte - Aumento da vegetação na Antártica - Crescimento da população de fitoplâncton na Antártica - Impactos negativos nas espécies não-migratórias do Ártico

13 Observed impacts of climate variations and attribution of causes in CA and SA.

14 YIELD IMPACT (% Change per Decade) Summary of estimated impacts of observed climate changes on yields over for four major crops in temperate and tropical regions th Percentile 75 th Percentile Median 25 th Percentile Wheat Soy Rice Maize 10 th Percentile CROP TYPE

15 VULNERABILITY AND EXPOSURE AROUND THE WORLD

16 ADAPTATION IS ALREADY OCCURING CLIMATE CHANGE REDUCING AND MANAGING RISKS SEVERE AND PERVASIVE IMPACTS INCREASING MAGNITUDES OF WARMING INCREASE

17 Climate-change adaptation as an iterative risk management process with multiple feedbacks. People and knowledge shape the process and its outcomes. SCOPING Identify Risks, Vulnerabilities, and Objectives Establish Decision- Making Criteria IMPLEMENTATION ANALYSIS Review and Learn Implement Decisions Identify Options Assess Risks Monitor Evaluate Tradeoffs

18 RISKS OF CLIMATE CHANGE INCREASE WITH CONTINUED HIGH EMISSIONS

19 Risk of climate-related impacts results from the interaction of climate-related hazards (including hazardous events and trends) with the vulnerability and exposure of human and natural systems. Changes in both the climate system (left) and socioeconomic processes including adaptation and mitigation (right) are drivers of hazards, exposure, and vulnerability.

20 PERCENTAGE OF YIELD PROJECTIONS Summary of projected changes in crop yields, due to climate change over the 21st century. The figure includes projections for different emission scenarios, for tropical and temperate regions, and for adaptation and no-adaptation cases combined. Relatively few studies have considered impacts on cropping systems for scenarios where global mean temperatures increase by 4oC or more. 100 Range of Yield Change % A NA Increase in Yield 25 50% 10 25% 5 10% 0 5% Decrease in Yield 0-5% -5-10% % % %

21 CLIMATE CHANGE CENTRAL AND SOUTH AMERICA OBSERVED AND PROJECTED IMPACTS

22 IPCC WG2, Chapter 21 (2014)

23 IPCC WG2, Chapter 21 (2014)

24 O SPM WG2 do quinto Relatório de Avaliação elaborado pelo painel da Organização das Nações Unidas e as informações são complementares ao primeiro capítulo do relatório, divulgado em setembro passado, que abordava A Base das Ciências Físicas. O segundo capítulo do relatório aponta que populações pobres que vivem em regiões costeiras podem sofrer com mortes e interrupções dos meios de subsistência devido ao aumento do nível do mar e que altas temperaturas em localidades semi-áridas poderão causar grandes perdas para agricultores com poucos recursos, o que aumentaria o risco de insegurança alimentar. Áreas tropicais da África, América do Sul e da Ásia devem sofrer com mais inundações, devido ao aumento de tempestades. Aquelas já vulneráveis, que registram constantemente enchentes e deslizamentos de terra, como o Sudeste do Brasil, podem sofrer graves consequências com o acréscimo do volume de chuvas. Sobre os recursos hídricos, o texto afirma que há fortes evidências de uma redução da oferta de água potável em territórios subtropicais secos, o que aumentaria disputas pelo uso de bacias hidrográficas algo semelhante ao que acontece atualmente entre os estados de São Paulo e Rio de Janeiro, com a disputa pelo uso da água do Rio Paraíba do Sul para abastecer o Sistema Cantareira. O texto estima também uma elevada perda de espécies de plantas e animais pela pressão humana, como a poluição e o desmatamento de florestas, além de redução dos recifes de corais no Caribe e costa de países tropicais, como o Brasil, por conta da acidificação, fenômeno causado pelo excesso de CO2 na atmosfera.

25 Clima do planeta e de todas as regiões está mudando. Vamos considerar apenas alguns exemplos do que aconteceu no Brasil do final de 2013 até agora: seca no semiárido do Nordeste; enchentes no Espírito Santo em Minas Gerais; escassez de chuvas e água no Sudeste; enchentes em Rondônia, Acre e Amazonas. Embora este o SPM WG2 não trate de cenários específicos para cada país, traz informações importantes sobre o que já vem mudando no clima regional e o que pode acontecer em cada continente. Brasil deve se preparar, como qualquer país, para mais eventos climáticos, cada vez mais extremos. Tudo o que observamos hoje - falta ou excesso de chuva, impactos na agricultura e saúde, perdas econômicas bilionárias - pode ser apenas uma amostra bem pequena do que vem por aí. E, na média, podemos esperar menos chuva em algumas regiões, como o já castigado semiárido, e aumento do índice anual de chuvas em outras, como o Sudeste e Sul do País. E a degradação ambiental, como o desmatamento, agrava ainda mais o panorama e os impactos. No melhor dos cenários, se não fizermos nada, podemos ver muitas pessoas perdendo seus bens, suas vidas, e imensos prejuízos para a economia local, regional e do país.

26 Central and South America could see increased risks to human health, problems with water availability in some regions, and flooding and landslides due to extreme precipitation in others, and decreased food production and quality.

27 Projected changes in annual average temperature and precipitation. CMIP5 multi-model mean projections of annual average temperature changes (left panel ) and average percent change in annual mean precipitation (right panel) for and under RCP2.6 and 8.5. Solid colors indicate areas with very strong agreement, where the multi-model mean change is greater than twice the baseline variability, and>90% of models agree on sign of change.

28 Summary of observed changes in climate and other environmental factors in representative regions of CA and SA. The boundaries of the regions in the map are conceptual (neither geographic nor political precision).

29 Observed impacts attributed to climate change reported in the scientific literature since the AR4. These impacts have been attributed to climate change with very low, low, medium, or high confidence, with the relative contribution of climate change to the observed change indicated (major or minor), for natural and human systems across eight major world regions over the past several decades.

30 Significant trends in precipitation and temperature have been observed in CA and SA (high confidence ). Besides, changes in climate variability and in extreme events have severely affected the region (medium confidence ). Climate projections suggest increases in temperature, and increases or decreases in precipitation for CA and SA by 2100 (medium confidence ). Changes in stream flow and water availability have been observed and projected to continue in the future in CA and SA, affecting already vulnerable regions (high confidence ). Land use change contributes significantly to environmental degradation exacerbating the negative impacts of climate change (high confidence ). Conversion of natural ecosystems is the main cause of biodiversity and ecosystem loss in the region, and is a driver of anthropogenic CC (high confidence ). Sea-level rise (SLR) and human activities on coastal and marine ecosystems pose threats to fish stocks, corals, mangroves, recreation and tourism, and control of diseases (high confidence ). Changes in agricultural productivity with consequences for food security associated to CC are expected to exhibit large spatial variability (medium confidence ). In many CA and SA countries, a first step toward adaptation to future climate changes is to reduce the vulnerability to present climate.

31 ADAPTATION IS ALREADY OCCURING

32 EFFECTIVE CLIMATE CHANGE ADAPTATION A MORE VIBRANT WORLD

33 Principles for Effective Adaptation Adaptation is place and context specific, with no single approach for reducing risks appropriate across all settings (high confidence). Adaptation planning and implementation can be enhanced through complementary actions across levels, from individuals to governments (high confidence). A first step towards adaptation to future climate change is reducing vulnerability and exposure to present climate variability (high confidence). Strategies include actions with cobenefits for other objectives. Adaptation planning and implementation at all levels of governance are contingent on societal values, objectives, and risk perceptions (high confidence). Recognition of diverse interests, circumstances, social-cultural contexts and expectations can benefit decision making processes. Existing and emerging economic instruments can foster adaptation by providing incentives for anticipating and reducing impacts (medium confidence). Constraints can interact to impede adaptation planning and implementation (high confidence). Poor planning, overemphasizing short-term outcomes, or failing to sufficiently anticipate consequences can result in maladaptation (medium evidence, high agreement).

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35 Adaptation is local.mitigation is a much more international response, because there s one singular problem, and there are a limited set of tools to address that. It doesn t matter where that carbon dioxide is produced or sucked out of the atmosphere. Adaptation is context specific. Uma seca como a que assola a Grande São Paulo além do Nordeste, da Austrália e da Califórnia e esvazia seus reservatórios é precisamente o tipo de fenômeno climático extremo previsto entre os impactos do aquecimento global Embora seja prematuro estabelecer uma relação de causa e efeito entre isso e aquilo, parece certo que a mensagem sobre riscos da mudança do clima encontra terreno mais fértil na proximidade de tais eventos.