Potential effects of climate change on inundation patterns in the Amazon Basin

Abstract

Abstract. Floodplain forests, namely the Várzea and Igapó, cover an area of more than 97 000 km 2 . A key factor for their function and diversity is annual flooding. Increasing air temperature and higher precipitation variability caused by climate change are expected to shift the flooding regime during this century, and thereby impact floodplain ecosystems, their biodiversity and riverine ecosystem services. To assess the effects of climate change on the flooding regime, we use the Dynamic Global Vegetation and Hydrology Model LPJmL, enhanced by a scheme that realistically simulates monthly flooded area. Simulation results of discharge and inundation under contemporary conditions compare well against sitelevel measurements and observations. The changes of calculated inundation duration and area under climate change projections from 24 IPCC AR4 climate models differ regionally towards the end of the 21st century. In all, 70 % of the 24 climate projections agree on an increase of flooded area in about one third of the basin. Inundation duration increases dramatically by on average three months in western and around one month in eastern Amazonia. The time of high-and low-water peak shifts by up to three months. Additionally, we find a decrease in the number of extremely dry years and in the probability of the occurrence of three consecutive extremely dry years. The total number of extremely wet years does not change drastically but the probability of three consecutive extremely wet years decreases by up to 30 % in the east and increases by up to 25 % in the west. These changes implicate significant shifts in regional vegetation and climate, and will dramatically alter carbon and water cycles.

Vulnerability and adaptive capacity of community food systems in the Peruvian Amazon: a case study from Panaillo

“…In this research, Panaillo community members and local institutions are already reporting significant challenges with food price fluctuations, diminishing incomes, and changes in climate, flora and fauna populations (Chapters 5-7). More severe flooding would likely destroy many tree and plant species (Santa Cruz et al, 2013;Langerwisch et al, 2013;, as illustrated in the 2010-2011 flooding event. Several studies project lower crop yield, increased soil erosion, reduced water availability, and increased plagues and diseases in response to changes in seasonality (Brondizio & Moran, 2008;Santa Cruz et al, 2013;Vegas de Cáceres, 2010).…”

“…Flood regimes will also change in response to higher air temperatures and increased precipitation variability. Langerwisch et al (2013) The impact of these climate changes would have significant repercussions for the flora and fauna in the area, including impacts on food networks and competition, reproductive cycles and plant phenology (Santa Cruz et al, 2013;Langerwisch et al, 2013;Vegas de Cáceres, 2010;. Davidson et al (2012) highlight that Amazonian species are accustomed to seasonal variability, but that extreme hydrological events could overwhelm the ecosystem's resilience.…”

Malaria in the State of Amazonas: a typical Brazilian tropical disease influenced by waves of economic development

“…It consists of low altitude topography and an equatorial climate and has high temperatures and high rainfall. The phenomena known as El Niño and La Niña are responsible for variations in weather patterns in the Amazon region (4) (5) . The vegetation consists predominantly of upland forests, fl oodplains, and fl ooded forests.…”

Estimating return periods for daily precipitation extreme events over the Brazilian Amazon

“…According to Gloor et al (2013), since 1990 there is an intensification of the Amazon hydrological cycle, with an increase of drainage during the rainy season and eventual severe droughts. Langerwisch et al (2013) have studied the effects of climatic changes on the flood regime of the Amazon Basin. These authors have used the Dynamic Global Vegetation and Hydrology Model LPJmL, enhanced by a scheme that realistically simulates monthly flooded area.…”