IPCC Climate Change Research Articles

Redefine Water Infrastructure Adaptation to a Nonstationary Climate

The statement “Climate stationarity is dead” by Milly et al. 2008 stresses the need to evaluate and when necessary, to incorporate nonstationary hydroclimatic changes into water resources and infrastructure planning and engineering. Variations of this theme echo in several other recent editorials by Rogers 2008 , Lettenmaier 2008 , and Werick and Palmer 2008 . The gravity of this topic was firmly felt among participants at a recent USEPA expert and stakeholder workshop on water infrastructure adaptation to climate change USEPA 2009 . Two questions remain at the core: 1 Is climate change “tangible” for consideration in water engineering and planning? and 2 if so, how can we develop “actionable science” for adaptation? In other words, can adaptation practice define the rate of hydroclimatic changes at local scales that are “tangible” and commensurate with other traditional engineering and planning variables? For “tangible” changes, how do we manage the risk arising from hydroclimatic projection uncertainties and justify the adaptation actions to the public and stakeholders? In this editorial, I will answer a “yes” to the first question and then argue for redefining the adaptation in the context of “how.” The adaptation need is laid out in many studies that have defined the magnitude and frequency of hydroclimatic changes using climate model simulations or statistical analysis of historical observations or both, although accurate future projections at a local scale remain elusive IPCC 2007; Bader et al. 2008; Fowler et al. 2007; Mearns et al. 2003 . According to the studies described in IPCC 2007 and references therein, global climate change has resulted in substantial warming of atmospheric temperature and a shifting of precipitation regimes in space and time. Such changes will accelerate in this century: a rise of 0.7°C 1.4°F in temperature over the past 100 years as compared to a greater projected increase of more than 4.0°C 2.4–6.4°C , or 7.2°F 4.3–11.5°F by 2100 in the worst-case A1F1 emission scenario Intergovernmental Panel on Climate Change IPCC 2007 . The impacts of these changes on water infrastructures and programs are apparent in several ways. Changes in hydrologic fluxes, water quantity, and quality of surface water and groundwater can affect the service functions of a water infrastructure that was designed and built under the assumption of climate stationarity. This compromise can occur in a nonstationary climate where the rate of future hydroclimatic change exceeds the statistical bounds of historical observations. An ongoing EPA study shows the precipitation in the contiguous United States has changed in the past century at a rate comparable to those of population changes; the latter is a traditional variable in the infrastructure planning and engineering. The two principal variables are often mismatched in spatial distribution, resulting in the imbalance of water demand

Potential effects of predicted climate change on the endemic South African Dwarf Chameleons, Bradypodion

The niche concept implies that a relationship exists between a species and its environment, while macro‐ecological theory suggests that an important attribute of a species’ environment is climate. Thus, changes in climate could affect individual species, but also communities. Here, we analysed the potential impacts of climate change on dwarf chameleons. A niche‐based modelling technique was used to predict current suitable climatic habitat for most Bradypodion species and for their phylogenetic clades. Additionally, the models were projected into the future (2080) using the IPCC climate change scenarios. All models for Bradypodion species and clades showed responses to predicted climate change, however, the degree and extent of these responses were individualistic. Most species responded with a contraction in predicated climatic suitability, but some registered an expansion or a shift. These results have important implications in understanding the vulnerability of biodiversity to climate change, and for the importance of considering the effects of predicted climatic shifts on the protection of biodiversity.

Tropical Forests and Climate Change Mitigation: The Global Potential and Cases from the Philippines

The Intergovernmental Panel on Climate Change IPCC Fourth Assessment report has highlighted the role of tropical forests in mitigating climate change. Deforestation, especially in tropical countries, contributes about 20 percent to total global greenhouse gas emissions. Development projects geared to reduce the rate of deforestation and forest degradation, and to establish forest plantations will help reduce greenhouse gases in the atmosphere, and significantly contribute to mitigating climate change. Three cases of forestry carbon projects underway in the Philippines are presented to illustrate the constraints facing project developers in undertaking these climate change mitigation efforts. Among the key lessons identified are: the difficulty in establishing land eligibility, the need for partners or buyers from industrialized countries to shoulder the transaction costs, and the crucial role of the local communities, including indigenous peoples, in the development effort.

Coping with Global Warming and Climate Change

The Intergovernmental Panel on Climate Change IPCC 2007, p. 9 has identified five key areas subject to impacts from increasing global average temperature: water, ecosystems, food, coasts, and health. A closer reading of the text of the IPCC report shows that many of the most serious impacts on the nonwater areas are, in fact, mediated via water. So, for instance, impacts on food are largely due to hydrological changes; in fact, aridity has major impacts on food, ecosystems, and human health. The pivotal role of water impacts, and hence water’s importance to adaptation, is also stressed in the Stern Report 2006 . Thinking about the relative issues involved in climate change, Mike Muller 2007 of the Global Water Partnership GWP said, “if it’s mitigation, then the focus is rightfully energy, and if it’s adaptation, it will be water resources!” By this he implied that the bulk of the mitigation strategies for climate change deal with handling the use of energy resources, while the adaptation strategies will be mostly driven by water concerns. Hence, we should focus on the water-adaptation strategies, bearing in mind that adaptation for other sectors may include many of the same, or similar, strategies.

Changing Northern Hemisphere Storm Tracks in an Ensemble of IPCC Climate Change Simulations

Abstract Winter storm-track activity over the Northern Hemisphere and its changes in a greenhouse gas scenario (the Special Report on Emission Scenarios A1B forcing) are computed from an ensemble of 23 single runs from 16 coupled global climate models (CGCMs). All models reproduce the general structures of the observed climatological storm-track pattern under present-day forcing conditions. Ensemble mean changes resulting from anthropogenic forcing include an increase of baroclinic wave activity over the eastern North Atlantic, amounting to 5%–8% by the end of the twenty-first century. Enhanced activity is also found over the Asian continent and over the North Pacific near the Aleutian Islands. At high latitudes and over parts of the subtropics, activity is reduced. Variations of the individual models around the ensemble average signal are not small, with a median of the pattern correlation near r = 0.5. There is, however, no evidence for a link between deviations in present-day climatology and deviations with respect to climate change.

Conservation of the rare British lichen Vulpicida pinastri: changing climate, habitat loss and strategies for mitigation

Abstract:Autecological information targeted towards rare and threatened lichen species is severely lacking. This study adopts the rare British lichen Vulpicida pinastri as a case study species and examines its ecological response to emerging threats: climate change and the recurrent loss of its primary habitat (juniper scrub). We used predictive niche modelling to examine the response of V. pinastri to a range of present-day climatic variables. A successful model was projected for a period during the 2050s based on IPCC climate change scenarios (UKCIP02 data), and threat was estimated as the proportional change in bioclimatic space. To estimate the potential range now and during the 2050s, projected bioclimatic space was masked by a habitat map equivalent to (i) the present-day distribution of juniper and (ii) theoretical juniper distribution based on existing rates of decline. Our results point to potential range loss of V. pinastri with climate warming, exacerbated by the recurrent decline in juniper habitat. This predictive modelling approach was complemented by an assessment of local stand-scale effects. At four sites in north-east Scotland we examined the occurrence and abundance of V. pinastri thalli, in response to juniper spatial distribution, and the life-stage and structure of individual shrubs. Vulpicida pinastri appeared to be dispersal limited at small-scales, and was significantly more abundant on old and degenerate juniper shrubs. Our results evidence a close relationship between management for habitat quality and effective lichen conservation. Effective conservation of V. pinastri must ensure cohorts of older and degenerate juniper shrubs are maintained at sites where the species is expected to be most resistant to long-term climate warming, i.e. in the uplands of north-east Scotland.

Frost in a future climate: modelling interactive effects of warmer temperatures and rising atmospheric [CO2] on the incidence and severity of frost damage in a temperate evergreen (Eucalyptus pauciflora)

AbstractAlthough plants are more susceptible to frost damage under elevated atmospheric [CO2], the importance of frost damage under future, warmer climate scenarios is unknown. Accordingly, we used a model to examine the incidence and severity of frost damage to snow gum (Eucalyptus pauciflora) in a sub‐alpine region of Australia for current and future conditions using the A2 IPCC elevated CO2 and climate change scenario. An existing model for predicting frost effects on E. pauciflora seedlings was adapted to include effects of elevated [CO2] on acclimation to freezing temperatures, calibrated with field data, and applied to a study region in Victoria using climate scenario data from CSIRO's Global Climate Model C‐CAM for current (1975–2004) and future (2035–2064) 30 years climate sequences. Temperatures below 0 °C were predicted to occur less frequently while the coldest temperatures (i.e. those below −8 °C) were almost as common in the future as in the current climate. Both elevated [CO2] and climate warming affected the timing and rates of acclimation and de‐acclimation of snow gum to freezing temperatures, potentially reducing the length of time that plants are fully frost tolerant and increasing the length of the growing season. Despite fewer days when temperatures fall below 0 °C in the future, with consequently fewer damaging frosts with lower average levels of impact, individual weather sequences resulting in widespread plant mortality may still occur. Furthermore, delayed acclimation due to either warming or rising [CO2] combined with an early severe frost could lead to more frost damage and higher mortality than would occur in current conditions. Effects of elevated [CO2] on frost damage were greater in autumn, while warming had more effect in spring. Thus, frost damage will continue to be a management issue for plantation and forest management in regions where frosts persist.

Simulated climate change impacts on fluxes of carbon in Norway spruce ecosystems along a climatic transect in Sweden

A simulation study based on recent regional climate scenarios for Sweden investigated possible changes in carbon (C) dynamics and net ecosystem exchange (NEE) of Swedish Norway spruce forest ecosystems. Four sites, representative of well-drained soils in four regions, were included. Stand development was simulated for a 100-year rotation period using a coupled model describing abiotic and biotic processes in the soil-plant-atmosphere system. Two IPCC climate change scenarios, corresponding to a mean annual temperature increase of about 2°C (A2) or 3°C (B2) from the reference period 1961–1990 to a new period 2061–2090, were considered. Annual maximum snow depth decreased with the increase in air temperature, whereas maximum soil frost depth and mean annual soil temperature showed only small changes, especially for the sites in northern Sweden. Simulations suggested that in the warmer climate, gross primary production (GPP) increased by 24–32% in northern Sweden and by 32–43% in the south. In the north, the increase was related to the combined effect of air and soil temperature extending the growing season, whereas in the south it was mainly governed by increased N availability due to increased soil temperature. NEE increased by about 20% (A2) or 25% (B2) at all sites, more or less solely due to increased accumulation of C in the tree biomass (including harvest residues), since changes in soil C were small compared with the current climate. Both light use efficiency and water use efficiency were improved in the future climate scenarios, despite increases in atmospheric CO2 not being considered.

Changing climate and historic‐woodland structure interact to control species diversity of the ‘Lobarion’ epiphyte community in Scotland

AbstractQuestion: How will changing climate and habitat structure interact to control the species diversity of lichen epiphytes?Location: Scotland.Method: Species richness (=diversity) of the epiphyte lichen community known as Lobarion (named after Lobaria pulmonaria) was quantified for 94 Populus tremula stands across Scotland, and compared in a predictive model to seven climate variables and eight measures of woodland structure. An optimum model was selected and used to project Lobarion diversity over the geographic range of the study area, based on IPCC climate change scenarios and hypothetical shifts in woodland structure.Results: Species diversity of the Lobarion community was best explained by three climate variables: (1) average annual temperature; (2) autumn and winter precipitation; in combination with (3) historic‐woodland extent. Projections indicate a positive effect of predicted climate change on Lobarion diversity, consistent with the physiological traits of cyanobac‐terial lichens comprising the Lobarion. However, the general response to climate is modified significantly by the effect on diversity of historic‐woodland extent.Conclusions: Historic‐woodland extent may exert an important control over local climate, as well as impacting upon the metapopulation dynamics of species in the Lobarion. In particular, a temporal delay in the response of Lobarion species to changed woodland structure is critical to our understanding of future climate change effects. Future Lobarion diversity (e.g. in the 2050s) may depend upon the interaction of contemporary climate (e.g. 2050s climate) and historic habitat structure (e.g. 1950s woodland extent). This is supported by previous observations for an extinction debt amongst lichen epiphytes, but suggests an extension of simple climate‐response models is necessary, before their wider application to lichen epiphyte diversity.

Modelling observed and future runoff from a glacierized tropical catchment (Cordillera Blanca, Perú)

Monthly runoff from the 34.3% glacierized tropical catchment of Llanganuco in the tropical Cordillera Blanca, Perú, is successfully simulated and compared with a measured 44 year time series. In the investigation area, the climate is characterized by all-year round homogenous temperature conditions and a strong variability in air humidity and moisture content of the atmosphere. Thus, contrary to the mid latitudes, the seasonal variation in glacier melt strongly depends on moisture-related variables, rather than on air temperature. The here presented ITGG-2.0-R model aims for these requirements. The lack of moisture-related input data other than precipitation demands for an intermediate calibration step. Net shortwave radiation, the emissivity of the atmosphere and a sublimation/melt ratio are related to precipitation amounts. Runoff is well simulated and correlates with the measured record with r 2 = 0.76. Seasonally obtained r 2 are only slightly smaller. On a long-term, the cumulative deviation is minor, and the mean annual cycle of runoff is reproduced rather well ( r 2 = 0.99). Based on four different IPCC climate change scenarios, future runoff is simulated. All runoff scenarios are modelled for the respective steady-state glacier extent. This leads to a reduction in the glacier size and a decreased amount of glacier melt. On the other hand, direct runoff increases due to larger glacier free areas. Consequently, mean annual runoff remains almost unchanged, but the seasonality intensifies considerably with more runoff during the wet and less runoff during the dry season.

Changing climate and historic-woodland structure interact to control species diversity of the ‘Lobarion’ epiphyte community in Scotland

Abstract Question: How will changing climate and habitat structure interact to control the species diversity of lichen epiphytes? Location: Scotland. Method: Species richness (=diversity) of the epiphyte lichen community known as Lobarion (named after Lobaria pulmonaria) was quantified for 94 Populus tremula stands across Scotland, and compared in a predictive model to seven climate variables and eight measures of woodland structure. An optimum model was selected and used to project Lobarion diversity over the geographic range of the study area, based on IPCC climate change scenarios and hypothetical shifts in woodland structure. Results: Species diversity of the Lobarion community was best explained by three climate variables: (1) average annual temperature; (2) autumn and winter precipitation; in combination with (3) historic-woodland extent. Projections indicate a positive effect of predicted climate change on Lobarion diversity, consistent with the physiological traits of cyanobacterial lichens compri...

Climate change impacts on groundwater resources: modelled deficits in a chalky aquifer, Geer basin, Belgium

An integrated hydrological model (MOHISE) was developed in order to study the impact of climate change on the hydrological cycle in representative water basins in Belgium. This model considers most hydrological processes in a physically consistent way, more particularly groundwater flows which are modelled using a spatially distributed, finite-element approach. Thanks to this accurate numerical tool, after detailed calibration and validation, quantitative interpretations can be drawn from the groundwater model results. Considering IPCC climate change scenarios, the integrated approach was applied to evaluate the impact of climate change on the water cycle in the Geer basin in Belgium. The groundwater model is described in detail, and results are discussed in terms of climate change impact on the evolution of groundwater levels and groundwater reserves. From the modelling application on the Geer basin, it appears that, on a pluri-annual basis, most tested scenarios predict a decrease in groundwater levels and reserves in relation to variations in climatic conditions. However, for this aquifer, the tested scenarios show no enhancement of the seasonal changes in groundwater levels.

Increased crop damage in the US from excess precipitation under climate change

Recent flooding and heavy precipitation events in the US and worldwide have caused great damage to crop production. If the frequency of these weather extremes were to increase in the near future, as recent trends for the US indicate and as projected by global climate models (e.g., US National Assessment, Overview Report, 2001, The Potential Consequences of Climate Variability and Change, National Assesment Synthesis Team, US Global Change Research Program, Washington, DC; Houghton et al., 2001, IPCC Climate Change 2001: The Scientific Basis, Third Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, 335pp.), the cost of crop losses in the coming decades could rise dramatically. Yet current assessments of the impacts of climate change on agriculture have not quantified the negative effects on crop production from increased heavy precipitation and flooding (Impacts of climate change and variability on agriculture, in: US National Assessment Foundation Document, 2001. National Assessment Synthesis Team, US Global Change Research Program, Washington DC.). In this work, we modify a dynamic crop model in order to simulate one important effect of heavy precipitation on crop growth, plant damage from excess soil moisture. We compute that US corn production losses due to this factor, already significant under current climate, may double during the next thirty years, causing additional damages totaling an estimated $3 billion per year. These costs may either be borne directly by those impacted or transferred to private or governmental insurance and disaster relief programs.

PACIFIC NORTHWEST REGIONAL ASSESSMENT: THE IMPACTS OF CLIMATE VARIABILITY AND CLIMATE CHANGE ON THE WATER RESOURCES OF THE COLUMBIA RIVER BASIN1

ABSTRACT: The Pacific Northwest (PNW) regional assessment is an integrated examination of the consequences of natural climate variability and projected future climate change for the natural and human systems of the region. The assessment currently focuses on four sectors: hydrology/water resources, forests and forestry, aquatic ecosystems, and coastal activities. The assessment begins by identifying and elucidating the natural patterns of climate vanability in the PNW on interannual to decadal timescales. The pathways through which these climate variations are manifested and the resultant impacts on the natural and human systems of the region are investigated. Knowledge of these pathways allows an analysis of the potential impacts of future climate change, as defined by IPCC climate change scenarios. In this paper, we examine the sensitivity, adaptability and vulnerability of hydrology and water resources to climate variability and change. We focus on the Columbia River Basin, which covers approximately 75 percent of the PNW and is the basis for the dominant water resources system of the PNW. The water resources system of the Columbia River is sensitive to climate variability, especially with respect to drought. Management inertia and the lack of a centralized authority coordinating all uses of the resource impede adaptability to drought and optimization of water distribution. Climate change projections suggest exacerbated conditions of conflict between users as a result of low summertime streamfiow conditions. An understanding of the patterns and consequences of regional climate variability is crucial to developing an adequate response to future changes in climate.

Near-future sea level impacts on coastal dune landscapes

Very little attention has been paid to the impact of global warming, especially sea level rise, on coastal dunescapes, despite the fact that these provide natural protection along many of the world's shorelines. This paper reviews likely responses given the IPCC climate change predictions to 2030AD, which include sea level rise in the order of 0.09 to 0.29m. It is envisaged that coastal dunes will react in a variety of ways dependent both on regional and local factors. Rising water levels will increase susceptibility to erosion, but the fate of released sediment, particularly the onshore/offshore partitioning, must depend on morphodynamic antecedence, and the propensity for periodic domain shifts. The release of material at the shoreline may allow construction of coastal dunes, to the point of progradation in some zones. The response of dune vegetation to a warmer, wetter climate is uncertain. Most of the main temperate dune species are C3 plants which given favourable conditions would respond positively to CO2 enhancement. However local factors may offset such potential gains.

IPCC's climate change mindset

IPCC's climate change mindset