1 / 46

Carlos A Nobre, Han Dolman, Gilvan Sampaio, Luiz Salazar, Marcos Oyama, José Marengo Centro de Ciência do Sistema Terre

The Possibility of Amazon Forest Savannization and Die-Back. Carlos A Nobre, Han Dolman, Gilvan Sampaio, Luiz Salazar, Marcos Oyama, José Marengo Centro de Ciência do Sistema Terrestre Instituto Nacional de Pesquisas Espaciais – INPE.

talon
Download Presentation

Carlos A Nobre, Han Dolman, Gilvan Sampaio, Luiz Salazar, Marcos Oyama, José Marengo Centro de Ciência do Sistema Terre

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Possibility of Amazon Forest Savannization and Die-Back Carlos A Nobre, Han Dolman, Gilvan Sampaio, Luiz Salazar, Marcos Oyama, José Marengo Centro de Ciência do Sistema Terrestre Instituto Nacional de Pesquisas Espaciais – INPE “Workshop: Sharing experiences in the design and implementation of climate change adaptation measures” Lima, Peru– 23 January 2009

  2. Risk Analysis of Amazon Forest Die-back Participating Institutions INPE, Brazil MRI, Japan Exeter University, UK PIK, Germany Science Program at the World Bank Latin America Region Walter Vergara, Co-ordinator

  3. Objective of Amazon Dieback Risk Analysis • Assist in understanding the risk, process and dynamics of Amazon dieback and its implications. • Support the analysis of long-term options that would be required to maintain the integrity of the basin. • Delivery date June 2009

  4. Does vegetation matter for the Earth System ? • The impacts of human activity on the Amazon rainforest could result in the collapse of large portions of the rainforest and significant loss of biodiversity within 30 to 50 years. • A comparison is made with similar events in the Saharan ecosystem, which was once a region of richer vegetation, before its abrupt collapse about 6000 years ago

  5. Vegetation partitions net radiation into more latent and less sensible heat (figure taken from Kabat et al.: Vegetation, Water, Humans, and the Climate, IGBP BAHC)

  6. Land=desert Land=forest ATMOSPHERE 71 000 km3 31 000 km3 421 000 km3 464 000 km3 410 000 km3 443 000 km3 137 000 km3 108 000 km3 37 000 km3 OCEANS CONTINENTS 28 000 km3 Remove vegetation from the continents  large changes will happen in the water cycle Kleidon et al. (2000)

  7. Biomes of tropical south America and precipitation seasonality Tropical Forest-Savanna Boundary Number of consecutive months with less than 50 mm rainfall Biomes of Brazil Tropical Forest Shrubland Savanna Annual Rainfall The importance of rainfall seasonality (short dry season) for maintaining tropical forests all over Amazonia Sombroek 2001, Ambio

  8. Evapotranspiration seasonality in the Amazon tropical forest and savanna Source: Rocha (2004) Forest Latent Heat flux (W m-2) mm day-1 Savanna Forest Net Radiation (W m-2) Savanna

  9. The Hypothesis of Amazonian ‘Savannization’ • Nobre et al. (1991) proposed that a post-deforestation climate in Southern Amazonia would be warmer, drier and with longer dry season, typical of the climate envelope of the tropical savanna (Cerrado) domain of Central South America. • ‘Savannization’ in this context is a statement on regional climate change and not intended to describe complex ecological processes of vegetation substitution.

  10. Modeling Deforestation and Biogeography in Amazonia Current Biomes Post-deforestation Nobre et al. 1991, J. Climate “1”Tropical Forest “6”Savanna

  11. Is the current Climate-Biome equilibrium in Amazonia the only stable equilibrium possible?

  12. Forest Savanna Two Biome-Climate Equilibrium States found for South America Current potential vegetation -- current state (a) -- second state (b) SoilMoisture Second State Results of CPTEC-DBM Initial Conditions : desert Rainfall anomalies Source: Oyama and Nobre, 2003

  13. Can global warming, deforestation, increased droughts and forest fires tip the current biome-climate equilibrium in the Amazon?

  14. Deforestation Climate Change Climate Extremes Fire The ecosystems of Amazonia are subjected to a suite of environmental drivers of change

  15. Tipping Points of the Climate System • Need to advance our understanding of critical tipping-points and hot-spot systems at risk, such as the Amazon. • The picture remains relatively scanty, with limited system-wide mapping of thresholds, cross-scale interactions and how system components reinforce each other amplifying the risk of crossing thresholds. Externally driven equilibrium change

  16. Question: Is there a “tipping point” of deforestation or global warming to induce ‘abrupt’ changes to the second biome-climate stable equilibrium?

  17. In 2007, total deforested area (clear-cutting) is 700,000 km2 in Brazilian Amazonia (18%) DEFORESTATION GLOBAL WARMING Anthropoenic and Natural Drivers of Environmental Change in Amazonia DROUGHTS FIRE Source: Greenpeace/Daniel Beltra

  18. I - LAND USE AND COVER CHANGE DEFORESTATION AND BURNING AROUND THE XINGU INDIGENOUS PARK, MATO GROSSO STATE, BRAZIL, 2004. Source: Tropical deforestation and climate change / edited by Paulo Moutinho and Stephan Schwartzman. -- IPAM - Instituto de Pesquisa Ambiental da Amazônia, 2005.

  19. PROJECTED LAND COVER CHANGE SCENARIOS 50% 20% Control 40% 60% 80% 100% or Soybean Sampaio et al., 2007 Source: Soares-Filho et al., 2006 - Amazon Scenarios Project, LBA

  20. 20% 40% 50% 60% 80% 100% 20% 40% 50% 60% 80% 100% Threshold of Deforestation at 40%! Controle Pastagem

  21. II – GLOBAL WARMING

  22. What are the likely biome changes in Tropical South America due to Global Warming scenarios of climate change?

  23. Cenários Climáticos globais para América do Sul Projeções de anomalias de temperatura (mm/dia) para América do Sul para o período de 2090-2099 (Cenário A2) em relação ao período base de 1961-1990 para 15 diferentes modelos climáticos globais disponíveis através do IPCC.

  24. Cenários Climáticos globais para América do Sul Projeções de anomalias de precipitação (mm/dia) para América do Sul para o período de 2090-2099 (Cenário A2) em relação ao período base de 1961-1990 para 15 diferentes modelos climáticos globais disponíveis através do IPCC.

  25. Climate Change Scenarios for Amazonia Results from 15 AOGCMs for the SRES A2 and B1 emissions scenarios, prepared for the IPCC/AR4. Models: BCCR-BCM2.0, CCSM3, CGCM3.1(T47), CNRM-CM3, CSIRO-MK3, ECHAM5, GFDL-CM2, GFDL-CM2.1, GISS-ER, INM-CM3, IPSL-CM4, MIROC3.2 (MEDRES), MRI-CGCM2.3.2, UKMO-HADCM3, ECHO-G

  26. Climate Change Consequences on the Biome distribution in tropical South America Projected distribution of natural biomes in South America for 2090-2099 from 15 AOGCMs for the A2 emissions scenarios, calculated by using CPTEC-INPE PVM. Salazar et al., 2007

  27. Climate Change Consequences on the Biome distribution in tropical South America 2020-2029 2050-2059 2090-2099 Grid points where more than 75% of the models used (> 11 models) coincide as projecting the future condition of the tropical forest and the savanna in relation with the current potential vegetation. The figure also shows the grid points where a consensus amongst the models of the future condition of the tropical forest was not found. for the periods (a) 2020-2029, (b) 2050-2059 and (c) 2090-2099 for B1 GHG emissions scenario and (d), (e) and (f) similarly for A2 GHG emissions scenario. SRES B1 SRES B1 SRES B1 SRES A2 SRES A2 SRES A2 Salazar et al., 2007 GRL (accepted)

  28. III - CLIMATE EXTREMES The impact of droughts

  29. Are hydrological extremes becoming more frequent? “The 2005 Western Amazon drought: one of the the most intense drought of the last 100”

  30. Anomalous enhancement of Hadley Cell-type circulation in September 2005 Descending motion over Amazonia: Inhibiting cloud and rain formation Tropical North Atlantic: warmer waters Amazonia Cox et al., 2008, Nature: This type of drought induced by latitudinal SST gradients in the Tropical Atlantic will become frequent in the future Cortesia: Jacy Saraira - SIPAM

  31. Use of the LPJ Vegetation Modelto study the impact of droughts on the Amazonian carbon cycle e.g. Stich et al., 2003

  32. Rainforest C-content “collapses” after a series of drier years but recovers when climate gets wet again

  33. High moisture High T hysteresis indicates effect of soil moisture memory Dry state Wet state Low moisture Low T Two stable states correspond to wet tropical humid and to dry tropical climates with tipping point of surface evaporation at 3.5 mm/day (current evaporation tropical rainforest 4-4.2 mm/day)

  34. In 2007, total deforested area (clear-cutting) is 700,000 km2 in Brazilian Amazonia (18%) + DEFORESTATION GLOBAL WARMING Anthropoenic and Natural Drivers of Environmental Change in Amazonia What are the synergistic impact of global warming + deforestation? Source: Greenpeace/Daniel Beltra

  35. Climate Change Scenarios + Projected Deforestation Scenarios 40% + Climate Change Scenarios from 15 AOGCMs for the SRES A2 and B1 emissions scenarios, prepared for the IPCC/AR4.Models: BCCR-BCM2.0, CCSM3, CGCM3.1(T47), CNRM-CM3, CSIRO-MK3, ECHAM5, GFDL-CM2, GFDL-CM2.1, GISS-ER, INM-CM3, IPSL-CM4, MIROC3.2 (MEDRES), MRI-CGCM2.3.2, UKMO-HADCM3, ECHO-G 60%

  36. Projected distribution of natural biomes in South America for 2050 from 15 AOGCMs for the B1 emissions scenario + projected land cover scenario with 40% of deforestation area for the Amazon

  37. Projected distribution of natural biomes in South America for 2100 from 15 AOGCMs for the A2 emissions scenario + projected land cover scenario with 60% of deforestation area for the Amazon

  38. Remaining Forest Area in Tropical South America (%) due to The combined effect of Global Warming and Deforestation

  39. Remaining Forest Area in Tropical South America (km2) due to The combined effect of Global Warming and Deforestation

  40. Total Area of Savanna in Tropical South America (%) due to The combined effect of Global Warming and Deforestation

  41. Total Area of Savanna in Tropical South America (km) due to The combined effect of Global Warming and Deforestation

  42. Main Conclusions on the future of biome distribution in Amazonia in face of land cover and climate changesI • The synergistic combination of regional climate changes caused by both global warming and land cover change over the next several decades, exacerbated by increased drought and forest fire frequency, could tip the biome-climate state to a new stable equilibrium with ‘savannization’ of parts of Amazonia and catastrophic species losses.

  43. Main Conclusions on the future of biome distribution in Amazonia in face of land cover and climate changesII • CO2 “fertilization” effects could increase forest resilience, but with less efficiency with continued warming and deforestation.

  44. Main Conclusions on the future of biome distribution in Amazonia in face of land cover and climate changesIII • Tentatively, we can say that thresholds for the maintenance of the rainforests are less than 4 C of global warming and less than 40% of total deforestation.

  45. MUCHAS GRACIAS!

  46. THANK YOU!

More Related