Why Should We Care About Climate Change?

by Caitlin Suh

Amy Davidson refers to a largely overlooked event called “The Great Famine” that happened in northern Europe in 1315-1317 as a prime example of the disastrous effects climate change and people’s disregard of it can have on humankind.

The famine started in 1315 when rain fell continuously for weeks on end. The foodcrops were spoiling and there was no way to make hay for livestock to eat. When the rains came again the next year and the next, up to a tenth of the population of some parts of Europe died from famine. However, according to Davidson, this specific event was never capitalized because the two events that followed were even worse; the Black Death in 1347 and the Hundred Years’ War that started in 1337, and because the Great Famine happened largely due to the weather, a “prosaic” cause. The seemingly never-ending rain became secondary to the focus on famine, leading people to blame the famine on ineptly farmed land instead of the weather. Today, the same sort of denouncement is seen in opponents of climate change, who pay no attention to, or even renounce climate change. But unlike in the past, there are many who come to the table with projections and the evidence to back it up. It is just a matter of choosing whether to listen or not. Continue reading

Scientists Link Colony Collapse Disorder to Stressed Young Bees

by Trevor Smith

Colony Collapse Disorder, which has troubled beekeepers across the nation and world over the last decade, has been linked this week to stressed young bees, The Guardian reports. Recent developments in bee populations have forced younger bees to leave the hive to forage much earlier than they might otherwise. The stress of these journeys is likely too much for the younger bees’ bodies, which have not finished fully developing; younger bees are not able to make as many journeys in their lives between the hive and the outer world as bees who leave the hive as adults. The result, argues an article in the latest issue of the Proceedings of the National Academy of Sciences of the United States of America (PNAS), is a hive-wide social imbalance that accelerates collapse (Perry et al. 2015). Continue reading

Just Released! “Energy, Biology, Climate Change”

FrontCover6x9 white border 72dpi EBCC2015

Our newest book, published on May 6, 2015 and available at Amazon.com for $19.95.

The focus of this book is the interactions between energy, ecology, and climate change, as well as a few of the responses of humanity to these interactions. It is not a textbook, but a series of chapters discussing subtopics in which the authors were interested and wished to write about. The basic material is cutting-edge science; technical journal articles published within the last year, selected for their relevance and interest. Each author selected eight or so technical papers representing his or her view of the most interesting current research in the field, and wrote summaries of them in a journalistic style that is free of scientific jargon and understandable by lay readers. This is the sort of science writing that you might encounter in the New York Times, but concentrated in a way intended to give as broad an overview of the chapter topics as possible. None of this research will appear in textbooks for a few years, so there are not many ways that readers without access to a university library can get access to this information.

This book is intended be browsed—choose a chapter topic you like and read the individual sections in any order; each is intended to be largely stand-alone. Reading all of them will give you considerable insight into what climate scientists concerned with energy, ecology, and human effects are up to, and the challenges they face in understanding one of the most disruptive—if not very rapid—event in human history; anthropogenic climate change. The Table of Contents follows: Continue reading

Distribution of West Nile Virus, United States

by Sarah King

West Nile virus (WNV) is a relatively new disease in North America, and consequently there is very little information available about how climate change will affect its distribution. In order to gain a better understanding, Ryan J. Harrigan and his colleagues modeled the incidence of the disease under current climate conditions (2003–2011) to predict how it will spread in the future (2013). The models proved to give a significantly accurate prediction for 2012 WNV distributions. They also projected the range of WNV for 2050 and 2080, which showed that predicted warmer temperatures and decreased precipitation would expand the range of WNV beyond its current bounds. The model and its predictive capabilities may help public health and policy officials prepare for and mitigate possible future outbreaks of WNV. Continue reading

Climatic Impacts on Japanese Encephalitis, Three Gorges Dam, China

by Sarah King

Japanese encephalitis (JE) is a prevalent, mosquito-borne infectious disease found throughout the Asian Pacific Rim and Southeast Asia and most predominately in China (Bai et al. 2014). The Chinese province Chongqing has one of the highest incidence rates of JE in the country in combination with only four other provinces, make up 50% of the incidence of JE in all of China, with only 26% of the population. Consequently, Chongqing is an interesting place to study the effect of climatic change on Japanese encephalitis, which is exactly what Yuntao Bai and his colleagues did. Bai and his team set out to identify the most important climatic variables that induce the transmission and spread of the JE virus in Chongqing from 1997–2008, and what kind of geographical incidence patters arise in relation to climate change (Bai et al., 2014). Continue reading

Behavior Alterations in Temperate Fish with Elevated-CO2

by Jennifer Fields

Anthropogenic CO2 emissions are causing an increase in dissolution of CO2 into the oceans resulting in ocean acidification. Teleost fish have been thought to have a high tolerance to ocean acidification because their specialized gills allow them to regulate the pH of their blood. However, recent studies have reported strong behavioral effects of ocean acidification in tropical coral reef species. The studies found that there was a diminishment of risk-assessment, learning, lateralization, and prey detection with increased dissolved CO2. But, little is known about the behavioral changes of temperate fish under the same conditions. Jutfelt et al. (2013) observed behavioral disturbances in boldness, exploratory behavior, lateralization, and learning in temperate fish under end of century ocean acidification conditions. The findings suggest that behavioral changes from increased CO2 are not limited to sensitive tropical species and could affect fish on a global scale by the end of the century. Continue reading

Asian Tiger Mosquito Targets Humans and Pets

by Emil Morhardt

As a follow-on to the previous post, this paper was just published a week ago and makes it clear that all the targets of Asian Tiger Mosquitos—transmitters of dengue, La Crosse, and chikungunya viruses in the Northeastern US—are mammals, and most of them are humans, cats, and dogs. Humans were targeted more in the suburbs, and cats in the cities. This is quite different from Culex mosquitos, another major vector of human diseases, which primarily feed on birds. Ari Faraji and his coauthors found this out by trapping mosquitos in central New Jersey, then sequencing the DNA in their blood meals. Mammalian blood constituted 84% of the meals, with humans making up 52%, cats 21%, and dog 12%. The rest came from mammals also, including, opossums, squirrels, rabbits, and deer.

Central New Jersey is at the northern limit of these mosquitos at the moment, but climate Continue reading

Asian Tiger Mosquitoes Expanding in Northeastern US

by Sarah King

Mosquitoes are known for dispersing many different kinds of diseases that affect human health. Asian tiger mosquitoes (Aedes albopictus), originating in Southeast Asia, are among the most invasive and widespread species of mosquitoes in the world. This species has been the cause of the reemergence of several mosquito-borne diseases such as chikungunya and dengue, and in the United States it is largely responsible for the reemergence of West Nile Virus. Using census information, temperature data, precipitation data, CO2 emissions forecasts, and generated maps of Ae. albopictus population distributions, Rochlin and his collgues (2013) statistically modeled projections of Ae. albopictus expansion through the next seventy years (2020s, 2050s, and 2080s). Their modeling shows that the range of Ae. albopictus will grow over the next seventy years to Continue reading

Future Risk of Barmah Forest Virus Disease, Queensland, Australia

 

Infectious diseases, particularly those that are transmitted by mosquitoes, are of special interest for public health officials because of the possible consequences of climate change on the incidence of such diseases. There are many different diseases that are of concern, such as dengue and malaria, but the one of focus for this paper is Barmah Forest Virus (BFV). On the coast of Queensland, Australia, Naish and her colleagues (2013) acquired data on the number of BFV cases, climate temperatures, rainfall levels, tidal levels, and socio-economic circumstances in the area during the years 2000—2008. In combination with climate prediction grids for 2025, 2050, and 2100, the analysts modeled possible BFV distributions at both the current climate levels and under possible forecasted climate changes, finding large expected changes in the BFV distribution. Predicting future locations of BFV occurrence can facilitate prevention planning.–Posted by Sarah King

Naish S., Mengersen K., Hu W., Tong S., 2013. Forecasting the Future Risk of Barmah Forest Virus Disease under Climate Change Scenarios in Queensland, Australia. PLoS ONE. Continue reading

The Effects of Climate Change and Socio-economic Development on the Global Distribution of Malaria

The global distribution of malaria has been linked to climatic and socioeconomic factors, which has caused researchers to study the effects of climate change and socioeconomic development; however, previous studies have failed to incorporate both these factors. Béguin et al. (2011) studied the influence of both climatic and socioeconomic factors on the past, present, and future distribution of malaria. A logistic regression model using temperature, precipitation, and gross domestic product per capita (GDPpc) was found to accurately identify recent distribution. Projections from a widely accepted climate change scenario, and an economic growth model were used. The models revealed that climate change increases malaria presence and distribution, while socioeconomic growth significantly decreases global distribution. However, it was found that the effects of climate change were much weaker than the effects of socioeconomic factors. –Simone Berkovitz

Béguin A, Hales S, Rocklöv J, Åström C, Louis V, Sauerborn R, 2011. The opposing effects of climate change and socio-economic development on the global distribution of malaria. Global Environmental Change 4: 1209—1214

The relationship between climatic factors and the prevalence of malaria vectors and parasite development has been established by numerous studies. Previous studies have assessed the influence of climate change on malaria, but Béguin et al. are the first to incorporate the combined influence of climatic and socio-economic factors. Climate and GDP per capita (GDPpc) both influence the risk of malaria, therefore it is necessary to distinguish and separate the two factors. The authors aimed to map the global distribution of malaria using empirical and logistic regression models, which incorporated both the effects of climate change and socioeconomic development.

In the study, Béguin et al. quantified the independent effects of climate change and socio-economic factors for the past and future malaria distribution. Current global malaria presence was determined using data from the World Health Organisation (WHO) and other researchers who estimated the risk and presence of both Plasmodium vivax and Plasmodium falciparum. In order to quantify socio-economic factors, GDP and population data, and future predictions of them were used in order to determine GDP per capita (GDPpc). The Climate Change scenario A1B developed for the IPCC special report was used as a basis for future predictions. Estimates for the years 1990, 2010, and 2050 were taken from a model developed by the Netherlands Environmental Assessment Agency, but in order to conduct a sensitivity analysis the predications were modified. A worst-case scenario, in which GPDpc declines, a scenario in which GDPpc is slightly reduced, and a scenario in which GDPpc remains constant at 2010 levels were used. To measure the effect of climate change, three different climate model simulations were used, which were statistically altered to fit a common temperature scale. In addition, temperatures recorded for the years 1991–2005 by the Climate Research Unit were used as a “no climate change” dataset. For each location, an average temperature and precipitation were calculated for the three past, present, and future time periods. In order to predict the probability that malaria will be present, Béguin et al. used a logistic regression model, with the presence of malaria as the outcome variable, and temperature, precipitation, and GDPpc as predictors. The most accurate model used the mean temperature of the coldest month and the mean temperature of the warmest month during the 1961–1990 period and the total annual GDP in a certain area divided by the population. These temperatures were used in order to indicate the “typical winter severity” and “intensity of the rainy season”.

Béguin et al. found the logistic regression model accurately identified the global malaria distribution for recent years. The test revealed a sensitivity of 85%, and a specificity of 95%; correctly classifying 85% of the data points in malarious-areas and 95% of the data points in malaria-free areas. In order to show the accuracy of the predictions, maps were created which diagramed correctly and incorrectly predicted absence or presence. In order to show the accuracy of the model, the first map used temperature and rainfall data together with GDPpc to compare the WHO data with the data calculated from the regression model. According to the world map diagram, the WHO data and the 1990 model were in agreement for most regions a few areas in the Middle East, Zambia, and Mexico.

When calculating the projected malaria risk, the fitted model parameters and the future projections of climate and GDP for the years 2030 and 2050 were used. Four scenarios were tested in order to differentiate between the climate and socioeconomic effects. The first scenario showed the effect of climate change without GDPpc growth, in which it was found the projected population at risk, is 5.2 billion. The second scenario predicted the effect of only GDPpc increase according to the A1B scenario and did not take into account climate change, which revealed only 1.74 billion would be at risk. The third scenario showed the combined effects of GDPpc increase and climate change, which revealed 1.95 billion people to be at risk. The fourth scenario showed the differences between the scenarios. In order to conduct sensitivity analysis, a range of economic situations were created, which resulted in a range of values produced.

The authors found that if global climate changed according to climate model predictions, but GDP remained constant, a modest expansion of malaria risk is predicted. If GDP changed as predicted by economic models, but climate change remained constant, much of the world, with the exception of Africa, would be malaria free. The authors note that the model was constructed on the basis of spatial patterns and does not account for year-to-year variability. However, Béguin et al were able to conclude that there is a strong relationship between GDPpc, climate, and malaria risk. Although climate change is a factor, socioeconomic development has the most dominant influence on the geographic contraction of malaria. Therefore, future economic developments could be most beneficial towards malaria risk mitigation.