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2013

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Articles 1 - 30 of 111

Full-Text Articles in Climate

Ice Crystal Formation And Evolution In Five Campaigns: Start08, Hippo Global, Dc3, Predict And Torero, Minghui Diao, Joshua Digangi, Anthony O’Brien, Mark Zondlo Dec 2013

Ice Crystal Formation And Evolution In Five Campaigns: Start08, Hippo Global, Dc3, Predict And Torero, Minghui Diao, Joshua Digangi, Anthony O’Brien, Mark Zondlo

Faculty Publications, Meteorology and Climate Science

In order to understand the microphysical properties of cirrus clouds, it is important to understand the formation and evolution of the environments where ice crystals form and reside on the microscale (~100 m). Uncertainties remain in simulating/parameterizing the evolution of ice crystals, which require more analyses in the Lagrangian view. However, most in situ observations are in the Eulerian view and are restricted from examining the lifecycle of cirrus clouds. In this work, a new method of Diao et al. GRL (2013)* is used to separate out five phases of ice crystal evolution, using the horizontal spatial relationships between ice …


Marine Diatom Assemblage Variation Across Pleistocene Glacial–Interglacial Transitions And Neogene Diatom Biostratigraphy Of Site C9001, Nw Pacific Ocean, Marcella K. Purkey Dec 2013

Marine Diatom Assemblage Variation Across Pleistocene Glacial–Interglacial Transitions And Neogene Diatom Biostratigraphy Of Site C9001, Nw Pacific Ocean, Marcella K. Purkey

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

In 2006, D/V-Chikyu cruise CK06-06 drilled Hole C9001C at Site C9001 in the Northwest Pacific Ocean, 80 km east of the Shimokita Peninsula, Japan. An existing chronostratigraphic framework provides a continuous glacial-interglacial (GI) climate record from which a diatom record of paleoenvironmental changes was developed across several GI cycles. Species counts, diatom temperature values, calculated sea-surface temperatures (SST) and factor analysis were produced for each sample and calibrated to prior diatom studies in this region. These features were used to characterize and compare interglacial maxima of Marine Isotope Stages (MIS) 1, 5e, 9 and 11 and transitions from the preceding …


Umphlett Qci Dec 2013, Natalie A. Umphlett Dec 2013

Umphlett Qci Dec 2013, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Soil Moisture

September Flooding in Colorado

Early October Blizzard

3-Month Precipitation and Temperature Outlooks

U.S. Seasonal Drought Outlook


Mass Bays Resource Inventory: Summary And Findings From The Review Of Plans And Assessments, Urban Harbors Institute, University Of Massachusetts Boston Dec 2013

Mass Bays Resource Inventory: Summary And Findings From The Review Of Plans And Assessments, Urban Harbors Institute, University Of Massachusetts Boston

Urban Harbors Institute Publications

The Massachusetts Bays Program (MBP) contracted with the Urban Harbors Institute (UHI) of the University of Massachusetts Boston to conduct a review of papers, presentations, reports, and other relevant material produced from 1996 (the last CCMP) to present, that might inform the MBP’s update of their Comprehensive Conservation and Management Plan (CCMP). The review focused on five topics identified as priority topics by the MBP: water quality, invasive species, climate change/vulnerability, continuity of estuarine habitat, and estuarine habitat protection in the geographic region of the Mass Bays Program, particularly the 47 nearshore estuaries and embayments identified in the 2012 MBP …


Biome Q10 And Dryness, Chuixiang Yi, Daniel Ricciuto, George Hendrey Dec 2013

Biome Q10 And Dryness, Chuixiang Yi, Daniel Ricciuto, George Hendrey

Publications and Research

Temperature sensitivity of soil respiration (Q10) is a critical parameter in carbon cycle models with important implications for climate-carbon feedbacks in the 21st century. The common assumption of a constant Q10, usually with a value of 2.0, was shown to be invalid by a previous model-data fusion study that reported biome-specific values of this parameter. We extend the previous analysis by demonstrating that these biome-level values of Q10 also are a function of dryness (R2 = 0.54). When tundra and cultivated lands are excluded, the correlation is much stronger (R2 = 0.92). Therefore …


Temperature Trends And Urban Heat Island Intensity Mapping Of The Las Vegas Valley, Adam Leland Black Dec 2013

Temperature Trends And Urban Heat Island Intensity Mapping Of The Las Vegas Valley, Adam Leland Black

UNLV Theses, Dissertations, Professional Papers, and Capstones

Modified urban climate regions that are warmer than rural areas at night are referred to as Urban Heat Islands or UHI. Islands of warmer air over a city can be 12 degrees Celsius greater than the surrounding cooler air. The exponential growth in Las Vegas for the last two decades provides an opportunity to detect gradual temperature changes influenced by an increasing presence of urban materials. This thesis compares ground based thermometric observations and satellite based remote sensing temperature observations to identify temperature trends and UHI areas caused by urban development.

Analysis of temperature trends between 2000 and 2010 at …


Impacts Of Climate Changes On The Spatiotemporal Distribution Of Precipitation In The Western United States, Peng Jiang Dec 2013

Impacts Of Climate Changes On The Spatiotemporal Distribution Of Precipitation In The Western United States, Peng Jiang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Precipitation in the Intermountain West is characterized by its great variability in both spatial and temporal distributions. Moreover, the spatiotemporal distribution of the precipitation is changing due to the climate changes. In this dissertation, three studies are conducted to investigate the multi-scale temporal variability of precipitation, the performance of current climate models on this variability, the influence of large-scale ocean oscillations on heavy precipitation, and the impact of human induced global warming on storm properties.

The first study is to examine the performance of current climate models on the simulation of the multi-scale temporal variability determined from the observed station …


Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca Dec 2013

Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

An assessment of the growth response of key vegetative species to climatic variability is vital to identifying possible local impacts on ecosystems faced with imminent climate change. With current climate projections in Nevada predicting a shift to an even more arid climate with greater year-to-year variability, the imperative exists to identify the effects of specific climatic controls on plant growth and to research methods to assess large-scale vegetative changes, especially in more remote areas where readily available data sets may be lacking. This study utilized annual growth ring indices constructed from big sagebrush (Artemisia tridentatassp.tridentata) stems collected in Spring Valley, …


Stable Isotope And Modelling Evidence For Co2 As A Driver Of Glacial-Interglacial Vegetation Shifts In Southern Africa, F. J. Bragg, I. C. Prentice, S. P. Harrison, G. Eglinton, P. N. Foster Nov 2013

Stable Isotope And Modelling Evidence For Co2 As A Driver Of Glacial-Interglacial Vegetation Shifts In Southern Africa, F. J. Bragg, I. C. Prentice, S. P. Harrison, G. Eglinton, P. N. Foster

Dartmouth Scholarship

Atmospheric CO2 concentration is hypothesized to influence vegetation distribution via tree-grass competition, with higher CO2 concentrations favouring trees. The stable carbon isotope (delta C-13) signature of vegetation is influenced by the relative importance of C-4 plants (including most tropical grasses) and C-3 plants (including nearly all trees), and the degree of stomatal closure - a response to aridity in C-3 plants. Compound-specific delta C-13 analyses of leaf-wax biomarkers in sediment cores of an offshore South Atlantic transect are used here as a record of vegetation changes in subequatorial Africa. These data suggest a large increase in C3 relative to C4 …


Observed Versus Gcm-Generated Local Tropical Cyclone Frequency: Comparisons Using A Spatial Lattice, Sarah Strazzo, Daniel J. Halperin, James Elsner, Tim Larow, Ming Zhao Nov 2013

Observed Versus Gcm-Generated Local Tropical Cyclone Frequency: Comparisons Using A Spatial Lattice, Sarah Strazzo, Daniel J. Halperin, James Elsner, Tim Larow, Ming Zhao

Publications

Of broad scientific and public interest is the reliability of global climate models (GCMs) to simulate future regional and local tropical cyclone (TC) occurrences. Atmospheric GCMs are now able to generate vortices resembling actual TCs, but questions remain about their fidelity to observed TCs. Here the authors demonstrate a spatial lattice approach for comparing actual with simulated TC occurrences regionally using observed TCs from the International Best Track Archive for Climate Stewardship (IBTrACS) dataset and GCM-generated TCs from the Geophysical Fluid Dynamics Laboratory (GFDL) High Resolution Atmospheric Model (HiRAM) and Florida State University (FSU) Center for Ocean–Atmospheric Prediction Studies (COAPS) …


Identification Of Extreme Precipitation Threat Across Midlatitude Regions Based On Short-Wave Circulations, Shih-Yu (Simon) Wang, Robert E. Davies, Robert R. Gillies Oct 2013

Identification Of Extreme Precipitation Threat Across Midlatitude Regions Based On Short-Wave Circulations, Shih-Yu (Simon) Wang, Robert E. Davies, Robert R. Gillies

Plants, Soils, and Climate Faculty Publications

The most severe thunderstorms, producing extreme precipitation, occur over subtropical and midlatitude regions. Atmospheric conditions conducive to organized, intense thunderstorms commonly involve the coupling of a low-level jet (LLJ) with a synoptic short wave. The midlatitude synoptic activity is frequently modulated by the circumglobal teleconnection (CGT), in which meridional gradients of the jet stream act as a guide for short Rossby waves. Previous research has linked extreme precipitation events with either the CGT or the LLJ but has not linked the two circulation features together. In this study, a circulation-based index was developed by combining (a) the degree of the …


Examining The Relationship Between Drought Development And Rapid Changes In The Evaporative Stress Index, Jason A. Otkin, Martha C. Anderson, Christopher Hain, Mark D. Svoboda Oct 2013

Examining The Relationship Between Drought Development And Rapid Changes In The Evaporative Stress Index, Jason A. Otkin, Martha C. Anderson, Christopher Hain, Mark D. Svoboda

National Drought Mitigation Center: Faculty Publications

In this study, the ability of a new drought metric based on thermal infrared remote sensing imagery to provide early warning of an elevated risk for drought intensification is assessed. This new metric, called the rapid change index (RCI), is designed to highlight areas undergoing rapid changes in moisture stress as inferred from weekly changes in the evaporative stress index (ESI) generated using the Atmosphere–Land Exchange Inverse (ALEXI) surface energy balance model. Two case study analyses across the central United States revealed that the initial appearance of negative RCI values indicative of rapid increases in moisture stress preceded the introduction …


Visiting Lecturer Will Link Public Health Risks To Climate Change, Public Affairs & News Bureau, Old Dominion University Oct 2013

Visiting Lecturer Will Link Public Health Risks To Climate Change, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.


Quantifying Risks Of Climate Change And Sea Level Rise To Naval Station Norfolk (Serdp Rc-1701), Kelly Burks-Copes Oct 2013

Quantifying Risks Of Climate Change And Sea Level Rise To Naval Station Norfolk (Serdp Rc-1701), Kelly Burks-Copes

October 2, 2013: Quantifying Risks and Moving Forward

No abstract provided.


Moving Forward: Next Steps For Confronting Increased Flood Risks, Molly Mitchell Oct 2013

Moving Forward: Next Steps For Confronting Increased Flood Risks, Molly Mitchell

October 2, 2013: Quantifying Risks and Moving Forward

No abstract provided.


Adaptive Planning For Flooding And Coastal Change In Virginia: Legal And Policy Issues For Local Government, Molly Mitchell Oct 2013

Adaptive Planning For Flooding And Coastal Change In Virginia: Legal And Policy Issues For Local Government, Molly Mitchell

October 2, 2013: Quantifying Risks and Moving Forward

No abstract provided.


Droughtscape, Fall 2013, National Drought Mitigation Center Oct 2013

Droughtscape, Fall 2013, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s report

Kansas community drought planning workshop November 5

Drought impacts webinars

Drought outlook and summary

Late summer drought brings more agricultural impacts

Plans help ranchers weather drought

NDMC contributions to U2U project

Drought Management Database archives strategies

QuickDRI will help spot flash droughts

NDMC Co-Hosts NASA workshop

Wilhite leads Integrated Drought Management Program work

Speaking of drought

Managing #Drought tweet chat transcript

Updated USDM website


Sea Level Rise, Spatially Uneven And Temporally Unsteady: Why The U.S. East Coast, The Global Tide Gauge Record, And The Global Altimeter Data Show Different Trends, Tal Ezer Oct 2013

Sea Level Rise, Spatially Uneven And Temporally Unsteady: Why The U.S. East Coast, The Global Tide Gauge Record, And The Global Altimeter Data Show Different Trends, Tal Ezer

CCPO Publications

Impacts of ocean dynamics on spatial and temporal variations in sea level rise (SLR) along the U.S. East Coast are characterized by empirical mode decomposition analysis and compared with global SLR. The findings show a striking latitudinal SLR pattern. Sea level acceleration consistent with a weakening Gulf Stream is maximum just north of Cape Hatteras and decreasing northward, while SLR driven by multidecadal variations, possibly from climatic variations in subpolar regions, is maximum in the north and decreasing southward. The combined impact of sea level acceleration and multidecadal variations explains why the global mean SLR obtained from similar to 20 …


Effects Of Ocean Acidification On The Behavior Of Two Marine Invertebrates: A Study Of Predator-Prey Responses Of The Molluscs Conus Marmoreus And Strombus Luhuanus At Elevated-Co2 Conditions, Jennifer Fields Oct 2013

Effects Of Ocean Acidification On The Behavior Of Two Marine Invertebrates: A Study Of Predator-Prey Responses Of The Molluscs Conus Marmoreus And Strombus Luhuanus At Elevated-Co2 Conditions, Jennifer Fields

Independent Study Project (ISP) Collection

Ocean acidification has been affecting the world’s oceans since the introduction of anthropogenic CO2 into the atmosphere during the Industrial Revolution. An increase in CO2 uptake from the atmosphere to the ocean has had a profound impact on not only the water chemistry, but marine organisms as well. Ocean acidification is known to have significant impacts on marine invertebrates in terms of calcification and reproduction; however, effects of increased CO2 on marine invertebrate behavior are vastly unknown. Marine conch gastropods have a modified muscularized foot that allows them to escape quite rapidly when faced with a predator cone shell. Utilizing …


Incorporating Satellite Derived Cloud Climatologies To Improve High Resolution Interpolation Of Daily Precipitation., Adam M. Wilson, Benoit Parmentier, Brian Mcgill, Rob Guralnick, Walter Jetz Sep 2013

Incorporating Satellite Derived Cloud Climatologies To Improve High Resolution Interpolation Of Daily Precipitation., Adam M. Wilson, Benoit Parmentier, Brian Mcgill, Rob Guralnick, Walter Jetz

Yale Day of Data

Conservation of biodiversity demands comprehension of evolutionary and ecological patterns and processes that occur over vast spatial and temporal scales. A central goal of ecology is to understand the factors that control the spatial distribution of species and this has become even more important in the face of climate change. However, at global scales there can be enormous uncertainty in environmental data used to model species distributions. Even ‘simple’ metrics such as mean annual precipitation are difficult to estimate in areas with few weather stations and available data sets do not quantify uncertainty in these surfaces. We are developing a …


Feeling The Heat? Substantial Variation In Temperatures Does Not Affect The Proportion Of Males Born In Australia, Barnaby J. Dixson, John Haywood, Philip J. Lester, Diane K. Ormsby Sep 2013

Feeling The Heat? Substantial Variation In Temperatures Does Not Affect The Proportion Of Males Born In Australia, Barnaby J. Dixson, John Haywood, Philip J. Lester, Diane K. Ormsby

Human Biology Open Access Pre-Prints

The global proportion of male births has been shown to vary with climate, with a higher proportion of male births documented in colder climates. Here we examined the hypothesis that ambient temperature predicts fluctuations in the proportion of male births in Australia and within seven Australian states using historical annual data spanning 1910-2009. We predicted that within states with tropical ambient temperatures the proportion of male births would decrease when ambient temperatures are higher. Considering the national composite births for the whole of Australia first, the proportion of males born ranged only from 0.510 to 0.517. We observed no relationship …


Issue Brief: Saving By Mitigating, University Of Louisville, New England Environmental Finance Center Sep 2013

Issue Brief: Saving By Mitigating, University Of Louisville, New England Environmental Finance Center

Sustainable Communities Capacity Building

Natural disasters can cause loss of life, inflict damage to buildings and infrastructure, and have devastating consequences for a community’s economic, social, and environmental well-being. Hazard mitigation means reducing damages from disasters.

Local governments have the responsibility to protect the health, safety, and welfare of their citizens. Proactive mitigation policies and actions help reduce risk and create safer, more disaster-resilient communities. Mitigation is an investment in your community’s future safety, equity, and sustainability.


Dynamical Downscaling Projections Of Twenty-First-Century Atlantic Hurricane Activity: Cmip3 And Cmip5 Model-Based Scenarios, Thomas R. Knutson, Joseph J. Sirutis, Gabriel A. Vecchi, Stephen Garner, Ming Zhao, Hyeong-Seog Kim, Morris Bender, Robert E. Tuleya, Isaac M. Held, Gabriele Villarini Sep 2013

Dynamical Downscaling Projections Of Twenty-First-Century Atlantic Hurricane Activity: Cmip3 And Cmip5 Model-Based Scenarios, Thomas R. Knutson, Joseph J. Sirutis, Gabriel A. Vecchi, Stephen Garner, Ming Zhao, Hyeong-Seog Kim, Morris Bender, Robert E. Tuleya, Isaac M. Held, Gabriele Villarini

CCPO Publications

Twenty-first-century projections of Atlantic climate change are downscaled to explore the robustness of potential changes in hurricane activity. Multimodel ensembles using the phase 3 of the Coupled Model Intercomparison Project (CMIP3)/Special Report on Emissions Scenarios A1B (SRES A1B; late-twenty-first century) and phase 5 of the Coupled Model Intercomparison Project (CMIP5)/representative concentration pathway 4.5 (RCP4.5; early- and late-twenty-first century) scenarios are examined. Ten individual CMIP3 models are downscaled to assess the spread of results among the CMIP3 (but not the CMIP5) models. Downscaling simulations are compared for 18-km grid regional and 50-km grid global models. Storm cases from the regional model …


Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen Sep 2013

Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946–1975; 1976–2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th century climate …


Sensitivity Of Limiting Hurricane Intensity To Sst In The Atlantic From Observations And Gcms, James Elsner, Sarah Strazzo, Thomas H. Jagger, Timothy Larow, Ming Zhao Aug 2013

Sensitivity Of Limiting Hurricane Intensity To Sst In The Atlantic From Observations And Gcms, James Elsner, Sarah Strazzo, Thomas H. Jagger, Timothy Larow, Ming Zhao

Publications

No abstract provided.


Ccaat/Enhancer-Binding Protein Delta (C/Ebp-Delta) Expression In Antarctic Fishes: Implications For Cell Cycle And Apoptosis, Isaac Martin Sleadd Aug 2013

Ccaat/Enhancer-Binding Protein Delta (C/Ebp-Delta) Expression In Antarctic Fishes: Implications For Cell Cycle And Apoptosis, Isaac Martin Sleadd

Dissertations and Theses

Chapter 1: Antarctic fishes are extremely cold adapted. Despite their inability to upregulate heat shock proteins, recent studies have demonstrated a capacity for heat response in these animals. A cDNA microarray study looked at the Notothenioid fish Trematomus bernacchii and revealed heat sensitivities for hundreds of genes, two of which code for members of the CCAAT/Enhancer-binding protein (C/EBP) family of transcription factors. These molecular switches are best known for their roles in apoptosis, inflammation and cell cycle arrest. This dissertation further elucidates the role of C/EBP-delta in the Antarctic fishes T. bernacchii and Pagothenia borchgrevinki.

Chapter 2: C/EBP-delta is constitutively …


Frequency, Intensity, And Sensitivity To Sea Surface Temperature Of North Atlantic Tropical Cyclones In Best-Track And Simulated Data, Sarah Strazzo, James B. Elsner, Jill C. Trepanier, Kerry A. Emanuel Aug 2013

Frequency, Intensity, And Sensitivity To Sea Surface Temperature Of North Atlantic Tropical Cyclones In Best-Track And Simulated Data, Sarah Strazzo, James B. Elsner, Jill C. Trepanier, Kerry A. Emanuel

Publications

Synthetic hurricane track data generated from a downscaling approach are compared to best-track (observed) data to analyze differences in regional frequency, intensity, and sensitivity of limiting intensity to sea surface temperature (SST). Overall, the spatial distributions of observed and simulated hurricane counts match well, although there are relatively fewer synthetic storms in the eastern quarter of the basin. Additionally, regions of intense synthetic hurricanes tend to coincide with regions of intense observed hurricanes. The sensitivity of limiting hurricane intensity to SST computed from synthetic data is slightly lower than sensitivity computed from observed data (5.561.31 m s21 (standard error, SE) …


The Influence Of Soil Organic Matter Stabilization Mechanisms On Carbon Mean Residence Time Within Various Ecosystems In The United States, Vicky Lynn Giese, Kate Heckman Phd Aug 2013

The Influence Of Soil Organic Matter Stabilization Mechanisms On Carbon Mean Residence Time Within Various Ecosystems In The United States, Vicky Lynn Giese, Kate Heckman Phd

STAR Program Research Presentations

Some terrestrial ecosystems and soils serve as carbon sinks, partially offsetting rising atmospheric CO2 levels. Physiochemical mechanisms of soil organic matter (SOM) stabilization affect how carbon stocks respond to global warming. In order to clarify the variance in SOM stabilization mechanisms across different soil types, SOM abundance, distribution and mean residence time (MRT) were compared for thirty-two soil samples from six ecosystems across the United States. Soils were previously described, collected and archived by the United States Geological Survey. Samples were processed by LLNL at the Center for Accelerator Mass Spectrometry (CAMS) using density fractionation to separate particulate organics …


A Paleoenvironmental Investigation Of Eolian Influx In Lacustrine Sediments Of The Southern Rocky Mountain Region, Rebecca L. Brice Aug 2013

A Paleoenvironmental Investigation Of Eolian Influx In Lacustrine Sediments Of The Southern Rocky Mountain Region, Rebecca L. Brice

Electronic Theses and Dissertations

Potential indications of long-term trends in paleoclimate, specifically winds, in the Southern Rocky Mountain region of the United States were tested using lacustrine sediment from South Blue Lake in the Wet Mountains of Colorado. This study builds upon existing eolian and lacustrine research, and investigates paleowind in a location not yet studied in this manner. Variability in sediment laminae, particle size, and mineralogy show similar patterns during the mid-Holocene warm period (ca. 5500 cal. yr BP - ca. 6000 cal. yr BP). These patterns indicate a warmer, drier, windier period that is contrasted by a less variable period in the …


Climate Change On The Prairie: A Basic Guide To Climate Change In The High Plains Region - Update, Lincoln, Ne Aug 2013

Climate Change On The Prairie: A Basic Guide To Climate Change In The High Plains Region - Update, Lincoln, Ne

High Plains Regional Climate Center: Staff Publications

Global Climate Change

Climate Change in the United States

Historical Climate Trends in the High Plains Region

Historical Climate Trends in the High Plains Region

High Plains Region Update: 2010-2012

New Tool: Climate Impact Reporter

Climate Change Projections and Possible Impacts

Climate Change Projections and Possible Impacts