Johanna Hoffman, a member of our Emerging Fellows program detects the causes of climate change in her second blog post. The views expressed are those of the author and not necessarily those of the APF or its other members.
Climate change comes in two forms. There is the kind caused by natural processes, and there is the kind created by humans. The former has been happening for millennia, produced by a range of factors from the sun’s energy output to shifts in the earth’s orbit. Since the late 18th century, however, that type of climate change has been supplanted. The industrial revolution and its innovations in manufacturing, production, transportation, power use, and more has led to rapid increases of pollutants, carbon dioxide and other emissions that trap heat in the atmosphere, known as greenhouse gases. For millennia, atmospheric carbon dioxide had never been above 325 parts per million. By 1950, levels had blown far past. Since then, massive changes in land use, such as the proliferation of parking lots and other paved surfaces, have made land absorb more sunlight, which our increasingly greenhouse gas filled atmosphere cannot adequately release. As a result, global temperatures continue to rise.
Most of this warming has occurred in the past 35 years, with the five warmest years on record all taking place since 2010. Much of this increased heat and greenhouse gas has been absorbed by our oceans. Since 1969, the top 700 meters of ocean water have warmed more than 0.22 degrees Centigrade and taken in 25% of emitted carbon dioxide. While these numbers may not seem drastic, the impacts are significant. The great ice sheets of the Artic, Antarctic and Greenland are melting at unprecedented rates, with some scientists predicting that the Arctic will be completely free of summer ice within fifteen years. This melting is not restricted to the poles. All across the globe, from the Alps to the Himalayas to the Andes and the Rockies, glaciers are retreating. Satellites show that spring snow cover in the Northern Hemisphere has declined over the last half century, with snow melts starting earlier, putting fresh water access for hundreds of millions at risk.
As glaciers have melted and ocean waters have warmed, seas have continued to rise. Today, seas are roughly 8 inches higher than they were in 1900, making many low-lying countries such as Bangladesh and the Maldives increasingly uninhabitable. A deadly side effect of this rising and warming is ocean acidification. As the ocean absorbs atmospheric CO2, it becomes more acidic in its chemistry. Over the last 150 years, the acidity of surface ocean waters has increased by about 30 percent, creating harsher environments for wide swaths of animal life. Cetaceans, fish species, crustaceans and more are all adversely affected by acidic conditions, threatening the lives and livelihoods of all those who rely on our oceans for sustenance and support.
The climatic changes spurring these shifts mean more than melting glaciers and rising seas. They mean that the current fires devastating the entire continent of Australia will become the norm in regions around the world. They mean that heat waves and severe storms will grow in intensity. They mean that floods will grow more frequent and more powerful, leaving more people inundated for longer periods of time. They mean that more drought will threaten more of our food supplies. They mean that the world that we knew is changing into some more unpredictable and more unwelcome to human habitation that we have ever seen before.
Posted By Johanna Hoffman,
Tuesday, January 7, 2020
Johanna Hoffman, a member of our Emerging Fellows program starts to publish a series of blog posts aimed at knowing how a changing climate will reshape the world order. This is her first post in our EF blog devoted to the importance of climate change. The views expressed are those of the author and not necessarily those of the APF or its other members.
Climate change is arguably both the hardest issue to grasp today and the most important to understand. Depending on location, it can manifest in everything from more violent forest fires to more intense storm seasons, to greater periods of drought. With sea levels slated to rise at least 4 ft. 7 in. (1.4m) meters by the end of the 21st century, coastal urban centers will suffer more flooding, groundwater infiltration, and storm surge. The climatic changes spurring sea level rise - a two-fold process of melting polar ice caps and expansion of warmer ocean waters - will result in greater climatological uncertainty across the board. Our cities will become hotter in summer and colder in winter, storms will wreak more damage in wetter parts of the world, and wildfires will regularly savage drier climates. Previously arable land will become unsuitable for growing crops and formerly perma-frosted regions will transition to breadbaskets. Spikes in particulate matter will make air harder to breathe. The scale of these changes will alter modern life as we know it.
As these events become more severe and more common, governments will face mounting pressures. Those with underdeveloped institutional capacity or thin layers of social capital will have growing difficulty supporting their populations, increasingly the likelihood for political strife and conflict. Numbers of environmental refugees are slated to rise significantly in coming decades, which will place more pressures on other parts of the world.
That climate change is predicted to create such degrees of damage and discord is a result of the fact that the systems supporting our current ways of life have become increasingly interconnected. Economic vitality is dependent on intricate patterns of international trade. Political instability in the Middle East has serious ramifications for policy in countries from the United States to Russia. More and more, access to fresh water, power and digital communications is dependent on cooperation and coordination between diverse and disparate parts of the world.
As such, climate change impacts in one region affect the systems, management and daily life in those of another. If another hurricane takes out power in a global financial center like New York City, as Hurricane Sandy did in 2012, global economies will feel the effect. Researchers have found that the violent civil war in Syria was brought on in part from an extreme drought between 2006 and 2009 that was most likely due to climate change. That war and the associated rise of groups like ISIS has affected life both in neighboring countries as well as those farther afield.
Judging by current strife around Syria, climate change is beginning to reshape our world order. In coming decades, it will likely continue to do so in deepening degrees, from public health to global trade and beyond. Many believe it stands to upend human existence as we know it. When we look towards our future on this planet, we can no longer expect what has been to be a model for what is to come. Understanding more about its potential reach and impact is critical to understanding how we want to respond.
Posted By Administration,
Monday, December 18, 2017
Updated: Sunday, February 24, 2019
Ariana Lutterman is one of our Emerging Fellows. She and our other Emerging Fellows will be posting throughout the year. Her first article seeks to clarify what climate change is and its implications for the present and the future.
Climate change is often cited as the most pressing problem facing humanity today. To truly understand its implications, it’s important to first understand its language. Here I hope to present a framework for how climate change has been defined through a process of international scientific consensus as well as how human actions are implicated in what we are currently observing as climate change.
Climate is weather over time, the earth’s climate is a combination of climates across the planet, and planetary climate change is a change in the earth’s climate over an extended period of time.
Phrased slightly differently, planetary climate change is a change in the combined climates made up of combined weather around the planet over a long period of time. Everyone anywhere experiences weather on a daily basis, and while everyone on the planet is affected by planetary climate change, its effects are infinitesimally small and often more intangible.
Global warming, a rise in the average global temperature, is one measure of planetary climate change. Often used interchangeably, global warming is just one measure of climate change. As the name suggests, it is an overall rise in planetary climate change, but this is only one aspect of what climate change means. The daily lived experience of climate change may, in many areas, look like cooler seasonal temperatures or more frequent cold weather events. So climate change as a term indicates that not only warming is occurring but also a host of other fluctuations to the usual planetary weather patterns.
The earth’s climate is constantly changing. Historically there have been periods both warmer and cooler than now. These fluctuations have resulted from natural processes like variations in Earth’s distance and energy received from the sun, volcanic eruptions, plate tectonics, and changes in earth’s oceans. There is a distinction between this natural climate change variability and what we are now observing. Current observable climate change is occurring much more rapidly than any historic climate event. It is this speed of change we are currently observing with which scientists are concerned. It is this that is attributed primarily to human activities.
The primary anthropogenic, or human-induced, contribution has been a dramatic increase in carbon dioxide (CO2) since industrial times largely through the burning of fossil fuels (oil, coal, natural gas). Though a misnomer (not actually the mechanism through which a greenhouse functions), the greenhouse effect describes how solar radiation trapped by a planet’s atmosphere warms the surface. Human actions since the industrial era have dramatically increased the number of atmospheric greenhouse gases. This anthropogenic greenhouse effect is caused primarily by actions like burning fossil fuels, agriculture, and deforestation which significantly increase atmospheric concentrations of carbon dioxide, methane, and nitrous oxide and cause higher than normal rates of solar radiation to become trapped by the atmosphere.
I plan to follow the international scientific community’s consensus in recognizing climate change as referring to planetary and anthropogenic changes to climatic patterns. Climate change is a part of a complex system of Earth processes, and its consequences manifest in similarly systemic ways. It represents not only an environmental crisis, but a social, economic, and cultural crisis as well.