scholarly journals Temporal and Spatial Change in Diameter Growth of Boreal Scots Pine, Norway Spruce, and Birch under Recent-Generation (CMIP5) Global Climate Model Projections for the 21st Century

Forests ◽  
2018 ◽  
Vol 9 (3) ◽  
pp. 118 ◽  
Author(s):  
Seppo Kellomäki ◽  
Harri Strandman ◽  
Tero Heinonen ◽  
Antti Asikainen ◽  
Ari Venäläinen ◽  
...  
Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1022 ◽  
Author(s):  
Yulian Liang ◽  
Yongli Wang ◽  
Yinjun Zhao ◽  
Yuan Lu ◽  
Xiaoying Liu

Floods have been experienced with greater frequency and more severity under global climate change. To understand the flood hazard and its variation in the future, the current and future flood hazards in the 21st century in China are discussed. Floods and their trends are assessed using the accumulation precipitation during heavy rainfall process (AP_HRP), which are calculated based on historical meteorological observations and the outputs of a global climate model (GCM) under three Representative Concentration Pathway (RCP) scenarios. The flood-causing HRPs counted by the flood-causing critical precipitation (the 60% fractile of AP_HRP) capture more than 70% of historical flood events. The projection results indicate that the flood hazards could increase under RCP4.5 and RCP8.5 and increase slightly under RCP2.6 during the 21st century (2011–2099). The spatial characteristics of flood hazards and their increasing trends under the three RCPs are similar in most areas of China. More floods could occur in southern China, including Guangdong, Hainan, Guangxi and Fujian provinces, which could become more serious in southeastern China and the northern Yunnan province. Construction of water conservancy projects, reservoir dredging, improvement of drainage and irrigation equipment and enhancement of flood control and storage capacity can mitigate the impacts of floods and waterlogging on agriculture.


2017 ◽  
Author(s):  
Behzad Asadieh ◽  
Nir Y. Krakauer

Abstract. Global warming is expected to intensify the Earth’s hydrological cycle and increase flood and drought risks. Changes in global high and low streamflow extremes over the 21st century under two warming scenarios are analyzed as indicators of hydrologic flood and drought intensity, using an ensemble of bias-corrected global climate model (GCM) fields fed into different global hydrological models (GHMs). Based on multi-model mean, approximately 37 % and 43 % of global land areas are exposed to increases in flood and drought intensities, respectively, by the end of the 21st century under RCP8.5 scenario. The average rates of increase in flood and drought intensities in those areas are projected to be 24.5 % and 51.5 %, respectively. Nearly 10 % of the global land areas are under the potential risk of simultaneous increase in both flood and drought intensities, with average rates of 10.1 % and 19.8 %, respectively; further, these regions tend to be highly populated parts of the globe, currently holding around 30 % of the world’s population (over 2.1 billion people). In a world more than 4 degrees warmer by the end of the 21st century compared to the pre-industrial era (RCP8.5 scenario), increases in flood and drought intensities are projected to be nearly twice as large as in a 2 degree warmer world (RCP2.6 scenario). Results also show that GHMs contribute to more uncertainties in streamflow changes than the GCMs. Under both forcing scenarios, there is high model agreement for significant increases in streamflow of the regions near and above the Arctic Circle, and consequent increases in the freshwater inflow to the Arctic Ocean, while subtropical arid areas experience reduction in streamflow.


2010 ◽  
Vol 19 (8) ◽  
pp. 1127 ◽  
Author(s):  
Yves Bergeron ◽  
Dominic Cyr ◽  
Martin P. Girardin ◽  
Christopher Carcaillet

Natural ecosystems have developed within ranges of conditions that can serve as references for setting conservation targets or assessing the current ecological integrity of managed ecosystems. Because of their climate determinism, forest fires are likely to have consequences that could exacerbate biophysical and socioeconomical vulnerabilities in the context of climate change. We evaluated future trends in fire activity under climate change in the eastern Canadian boreal forest and investigated whether these changes were included in the variability observed during the last 7000 years from sedimentary charcoal records from three lakes. Prediction of future annual area burned was made using simulated Monthly Drought Code data collected from an ensemble of 19 global climate model experiments. The increase in burn rate that is predicted for the end of the 21st century (0.45% year–1 with 95% confidence interval (0.32, 0.59) falls well within the long‐term past variability (0.37 to 0.90% year–1). Although our results suggest that the predicted change in burn rates per se will not move this ecosystem to new conditions, the effects of increasing fire incidence cumulated with current rates of clear‐cutting or other low‐retention types of harvesting, which still prevail in this region, remain preoccupying.


2017 ◽  
Vol 21 (11) ◽  
pp. 5863-5874 ◽  
Author(s):  
Behzad Asadieh ◽  
Nir Y. Krakauer

Abstract. Global warming is expected to intensify the Earth's hydrological cycle and increase flood and drought risks. Changes over the 21st century under two warming scenarios in different percentiles of the probability distribution of streamflow, and particularly of high and low streamflow extremes (95th and 5th percentiles), are analyzed using an ensemble of bias-corrected global climate model (GCM) fields fed into different global hydrological models (GHMs) provided by the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) to understand the changes in streamflow distribution and simultaneous vulnerability to different types of hydrological risk in different regions. In the multi-model mean under the Representative Concentration Pathway 8.5 (RCP8.5) scenario, 37 % of global land areas experience an increase in magnitude of extremely high streamflow (with an average increase of 24.5 %), potentially increasing the chance of flooding in those regions. On the other hand, 43 % of global land areas show a decrease in the magnitude of extremely low streamflow (average decrease of 51.5 %), potentially increasing the chance of drought in those regions. About 10 % of the global land area is projected to face simultaneously increasing high extreme streamflow and decreasing low extreme streamflow, reflecting the potentially worsening hazard of both flood and drought; further, these regions tend to be highly populated parts of the globe, currently holding around 30 % of the world's population (over 2.1 billion people). In a world more than 4° warmer by the end of the 21st century compared to the pre-industrial era (RCP8.5 scenario), changes in magnitude of streamflow extremes are projected to be about twice as large as in a 2° warmer world (RCP2.6 scenario). Results also show that inter-GHM uncertainty in streamflow changes, due to representation of terrestrial hydrology, is greater than the inter-GCM uncertainty due to simulation of climate change. Under both forcing scenarios, there is high model agreement for increases in streamflow of the regions near and above the Arctic Circle, and consequent increases in the freshwater inflow to the Arctic Ocean, while subtropical arid areas experience a reduction in streamflow.


2013 ◽  
Vol 20 (1) ◽  
Author(s):  
Krzysztof Błażejczyk ◽  
Danuta Idzikowska ◽  
Anna Błażejczyk

AbstractThis paper presents the results of research dealing with forecast changes in the frequency of occurrence of heat and cold stress in Warsaw (Poland) in the years 2001-2100, and the possible influence these may exert on mortality risk. Heat and cold stress were assessed by reference to the U niversal T hermal C limate I ndex (UTC I), for which values were calculated using meteorological data derived from the MPI-M-RE MO regional climate model, at a with spatial resolution of 25 × 25 km. The simulations used boundary conditions from the EC HAMP5 Global Climate Model, for SRES scenario A1B. Predictions of mortality rate were in turn based on experimental epidemiological data from the period 1993-2002. Medical data consist of daily numbers of deaths within the age category above 64 years (TM64+). It proved possible to observe a statistically significant relationship between UTC I and mortality rates, this serving as a basis for predicting possible changes in mortality in the 21st century due to changing conditions as regards heat and cold stress.


2021 ◽  
Author(s):  
Lizz Ultee ◽  
Sloan Coats ◽  
Jonathan Mackay

Abstract. Global climate model projections suggest that 21st century climate change will bring significant drying in the terrestrial midlatitudes. Recent glacier modeling suggests that runoff from glaciers will continue to provide substantial freshwater in many drainage basins, though the supply will generally diminish throughout the century. In the absence of dynamic glacier ice within global climate models (GCMs), a comprehensive picture of future drought conditions in glaciated regions has been elusive. Here, we leverage the results of existing GCM simulations and a global glacier model to evaluate glacial buffering of droughts in the Standardized Precipitation-Evapotranspiration Index (SPEI). We find that accounting for glacial runoff tends to increase multi-model ensemble mean SPEI and reduce drought frequency and severity, even in basins with relatively little glacier cover. Glacial drought buffering persists even as glacial runoff is projected to decline through the 21st century.


1996 ◽  
Author(s):  
Larry Bergman ◽  
J. Gary ◽  
Burt Edelson ◽  
Neil Helm ◽  
Judith Cohen ◽  
...  

2010 ◽  
Vol 10 (14) ◽  
pp. 6527-6536 ◽  
Author(s):  
M. A. Brunke ◽  
S. P. de Szoeke ◽  
P. Zuidema ◽  
X. Zeng

Abstract. Here, liquid water path (LWP), cloud fraction, cloud top height, and cloud base height retrieved by a suite of A-train satellite instruments (the CPR aboard CloudSat, CALIOP aboard CALIPSO, and MODIS aboard Aqua) are compared to ship observations from research cruises made in 2001 and 2003–2007 into the stratus/stratocumulus deck over the southeast Pacific Ocean. It is found that CloudSat radar-only LWP is generally too high over this region and the CloudSat/CALIPSO cloud bases are too low. This results in a relationship (LWP~h9) between CloudSat LWP and CALIPSO cloud thickness (h) that is very different from the adiabatic relationship (LWP~h2) from in situ observations. Such biases can be reduced if LWPs suspected to be contaminated by precipitation are eliminated, as determined by the maximum radar reflectivity Zmax>−15 dBZ in the apparent lower half of the cloud, and if cloud bases are determined based upon the adiabatically-determined cloud thickness (h~LWP1/2). Furthermore, comparing results from a global model (CAM3.1) to ship observations reveals that, while the simulated LWP is quite reasonable, the model cloud is too thick and too low, allowing the model to have LWPs that are almost independent of h. This model can also obtain a reasonable diurnal cycle in LWP and cloud fraction at a location roughly in the centre of this region (20° S, 85° W) but has an opposite diurnal cycle to those observed aboard ship at a location closer to the coast (20° S, 75° W). The diurnal cycle at the latter location is slightly improved in the newest version of the model (CAM4). However, the simulated clouds remain too thick and too low, as cloud bases are usually at or near the surface.


Sign in / Sign up

Export Citation Format

Share Document