Climate change has consequences

5_1_image01new.jpgAs we’ve seen, climate change is happening everywhere. It not only affects the natural systems of our planet, but climate change also has big impacts on communities around the globe, from small towns to big cities. Many people have already had to deal with major challenges including sea level rise, hurricanes, severe drought, and damaging fires and floods. Extreme weather events can affect travel, health, food production, and our daily livelihoods. In severe cases, climate change can also lead to forced migration of people, disease, damaged homes and highways, the loss of crops and loss of access to clean water.

Climate change doesn’t differentiate between who may be affected— all of us are vulnerable to the impacts. In some cases, the people who are the most affected are those least responsible for recent climate change, such as small island nations that have very low carbon emissions but face some of the greatest threats of sea level rise. Even something occurring seemingly far away can impact us at home, like when a severe drought in California affects the foods we can buy at the market. As you have seen in the previous chapters, this is because many of our ecosystems and economies are linked. Damage in one part of the world has repercussions in other places as well.

Throughout this chapter, we will explore some of the major impacts of climate change on people and places around the globe. In the future, many more people may face entirely new weather and unexpected climate extremes. We will learn that we all need to prepare for more challenges in the future, no matter where we live.


 Connecting climate change and extreme events

In the introduction, we learned that weather is the day-to-day variation of the atmosphere that includes temperature, clouds, precipitation, wind, and other elements such as humidity levels. Climate is the average of weather patterns over time. Climate also includes weather extremes, such as floods, blizzards, and drought. The frequency of weather extremes is one major difference between different climates across the globe. In some geographic areas, such as sub-Saharan Africa, it is expected to be very dry and hot, but if those same extremes occurred in northern Europe, then we would certainly become alarmed. We begin to question when we see unusual extreme weather, such as multiple hurricanes or year after year of excessively long droughts. Some people call this kind of extreme a climate anomaly — meaning that something is occurring that is different than usual.

We’ve learned that scientists look at long-term records to see changes already occurring in the atmosphere, oceans and ice. As the climate continues to change, it directly impacts the energy balance of the planet and the day-to-day weather as well. The recent rise in temperatures influences how weather systems behave. Take a look at this video to be reminded of the increase in global temperatures around the world over recent years. If we continue to see extreme events in the coming decades, then we will know that our baselines (or usual behavior) for both climate and weather systems have shifted. This means that we may regularly expect extreme events and shifts in our climate systems, sometimes when we least anticipate them.

Scientists are studying the relationship between extreme events and climate change to see if such events may become more frequent or more severe. We do know that as climate continues to change in the long term, weather will also be directly affected. The Intergovernmental Panel on Climate Change (IPCC) recently released a special report on extreme events and found some key linkages with climate change. We can expect that there will be increased extremes in heat, precipitation, the wind speeds of tropical storms, and wildfire risk. This really alerts us that climate change is a big deal for all of us. Take a look at all the climate anomalies that occurred around the world in 2013 alone.


 What to expect: A look at extreme events

Climate change can cause unexpected results. These may not be obvious until an increase in severe storms occurs; weather patterns are altered, and coastal flooding increases. The IPCC reported an increase in the frequency of extreme events since 1950, and we can expect more to occur. This graph of weather-related disasters from 1980 to 2012 shows that natural disasters are on the rise all over the globe. You’ll also see that these disasters come at a very high cost. The other graph shows a billion dollars worth of damage from extreme events in 2013 alone in the United States.



EXTREME STORMS: Hurricane Alert!

Hurricanes are one example of extreme weather that has a major impact – and one that can be pretty damaging. Hurricanes are big and powerful windstorms. They form only in very warm and wet conditions, typically over the ocean in tropical areas. Hurricanes can grow to be hundreds of miles wide, and the winds are so strong that if they hit land they may destroy anything in their path. The wind speed determines how potentially dangerous a storm is, and it is rated by the Saffir-Simpson Scale, which goes from 1 to 5. Category 5 means the winds are over 157 miles per hour! With climate change, an IPCC special report on extreme events states that the average wind speed of hurricanes will likely increase in some areas– that’s not very good news for people in a hurricane's path. When a hurricane moves over land, it loses some of its moisture and wind speed, until it eventually dies down. But unfortunately, this can often occur too late, after much damage has already been done. When any hurricane hits land, the results are often damaging and even catastrophic. 


The World Meteorological Organization is in charge of naming hurricanes. The names are chosen from a list of names that are alphabetically ordered from A to W. What happened to X, Y and Z? Well maybe they couldn’t think of enough names beginning with those letters so they aren’t included; neither are Q and U. There are a total of six lists, which are recycled every six years. If a storm is too devastating, like Katrina in 2005, then its name is removed from the list. Each year, the first hurricane of the season is named the A name, the second storm gets the B name, and so on. For example, in 2014, we have Hurricanes Arthur, Bertha and Cristobal to start the season. Can you find your name on the list?


The only difference between these three names for tropical storms is the location where a storm occurs. In the Atlantic and Northeast Pacific, the term hurricane is used. Typhoons occur in the Northwest Pacific, and cyclones occur in the South Pacific and Indian oceans.






Hurricanes are huge and powerful windstorms that gather their energy through contact with warm waters. The water has to be about 80°F (26°C) or warmer, which is why warming sea surface temperatures also make the conditions more ideal for hurricanes to form. Warm waters also cause greater evaporation, generating clouds. The warm and humid air has very low pressure, so cooler winds spiral toward it. The moist air rises higher and condenses into thick clouds. The wind blows the clouds into a spiral. In the center is the “eye” of the storm, which is the calmest part, with the lightest winds. Just outside this calm portion is the eye wall, where the winds are the strongest and rainfall the heaviest. An eye wall is the most destructive part of the hurricane and where the wind speed is the highest. A storm surge is a big mound of water that piles up as the hurricane spirals around. This can be especially devastating when it hits land.

Watch the video to see all the hurricanes forming near the Gulf Coast in 2012, the year that Hurricane Sandy struck the eastern United States.


and too little

According to the IPCC report, we can expect to see more extreme events related to precipitation. Scientists say it is very likely that the frequency of heavy precipitation will increase over the course of the 21st century. This means that many places will see more torrential and unexpected downpours, which may lead to flooding. Flooding affects everything! It comes from having too much rain and is often associated with hurricanes and tropical storm events. It can result in a cutoff of our basic services, like communication, power, and transportation, or even inundate our homes and businesses with water.

While some areas may experience more rain, the IPCC also says that some areas may be more vulnerable to intensifying droughts in the next century. These places include southern and central Europe, central North America, Central America and Mexico, northeast Brazil, and southern Africa. Waiting for rain can be just as devastating as too much rain. Drought is defined as below-normal levels of rivers, lakes and groundwater. Farmers are especially hard hit when the rains don’t come. A lot of agricultural production occurs in the tropics and subtropics, where there has been less and less precipitation in recent years. Areas of Africa, Asia, the Mediterranean, and the U.S. are already getting drier and drier each year.

Too much or too little rain threatens global food production, affecting fruits, vegetables, grain, livestock and fisheries around the world. During a drought, there may be lower crop yields and greater water needs for irrigation. California is one of the largest producers of fruits and vegetables for the U.S., and the state is experiencing the hottest year on record in 2014. This is after three years of below-normal rainfall for the state. This means that huge areas of land will remain fallow (un-planted), massive job loss, and billions of dollars will be lost by agriculture businesses.



EXTREME TEMPERATURES: Too hot, too cold!

Summer heat

We can also expect that daily temperature extremes will occur, especially during the summer. The IPCC finds that heat waves will increase in length, frequency, and intensity. A heat wave is a long period of excessively hot weather. People can suffer from heatstroke or get very dehydrated if they spend time outside during a heat wave. Heat waves also result in an increase in electricity use because many people turn on their air conditioning to cool their homes and businesses. Power outages have occurred in parts of California, Texas, and Australia when too many people were running their air conditioning. These extreme temperatures also damage crops and dry up local water sources. Lakes in Texas have completely dried up during heat waves, which made summer boating impossible. Recent heat waves have hit Russia (2010), Texas (2011) and Australia (2012). Average summer temperatures are increasing all over the globe, as you see in the graph here.



Fire Alert!

Warming temperatures and drought conditions make forests more susceptible to fires. Devastating fires have struck many states in the western United States in the last few years. We learned in the last chapter that keeping our forests healthy is key to reducing the risk of fire, and unfortunately, as the climate warms the forests are getting drier and more susceptible to pest infestations and fire. With ongoing climate change, scientists expect the fire season to get longer and more outbreaks to occur. Many families have lost their homes to fire. This is definitely something we want to prevent as much as possible.

Winter freeze

In some places, very cold events are occurring that are very unexpected. In January 2014, the Midwest and the eastern United States experienced the impacts of the polar vortex. This occurs when cold air from the North Pole extends to lower latitudes for days to weeks, bringing freezing temperatures. When the air patterns meander like this, then warmer temperatures can occur farther north, like in Alaska and northern Canada. Basically, weather patterns are getting out of sync, and the extreme polar vortex event is a good example of this. Take a look at our science video where we learn where the polar jet stream comes from and how it impacts our weather.



 Water around the world:
 Rising seas and water scarcities

5_4_image_01.jpgWhat if your entire home or neighborhood went underwater? It may seem crazy to imagine, but that is exactly what many island communities are facing. We learned previously that warming temperatures and melting glaciers are causing sea levels to rise. These changes are already having major impacts on small islands and many coastal populations.

Many island states have a really low elevation and smaller size, especially those in the Pacific and Indian Oceans. Some of the most vulnerable islands are the Marshall Islands, Kiribati, Tuvalu, Tonga, Micronesia, the Cook Islands, Antigua, Nevis, and the Maldives. These islands are dealing with coastal erosion, sea flooding and saline intrusion into their local water systems. As the sea level continues to rise, many are threatened with becoming entirely underwater.  




Tuvalu (too-VAH-loo), one of the smallest countries in the world, is a tiny nation located in the Pacific Ocean, between Hawaii and Australia. Tuvalu is made up of three reef islands and six atolls. Atolls are ring-shaped coral reefs with water or a lagoon in the center. About 11,000 people live in Tuvalu. The highest point on the island is only 4.6 meters (15 ft) above sea level! This means sea level rise is going to have a major impact immediately. Some predict that Tuvalu could be submerged within the next 50 years. The islands will literally disappear under the water, displacing all the people who live there. This means that the people of Tuvalu will have to look for a new place to live altogether. In the meantime, daily life on the islands is not getting any easier as the rising seas are leading to coastal erosion and are also contaminating the freshwater on the islands, making it too salty to drink.

Many of the people living on Tuvalu obviously are very concerned about the future and climate change. They have been actively engaged in meeting at the United Nations to make an effort to encourage cuts in carbon emissions around the world. They’ve joined forces with many other small island nations to raise awareness of the severity and urgency of climate change, and especially sea level rise.


While there may be a lot of water in the ocean, there may be too little fresh water on land. Water scarcity is a major concern because of population growth and climate change. More people means that we need more water, but water use is actually growing at twice the rate of the population. Water scarcity happens when there is a greater demand for water, from people and the environment, than what is available. Around 700 million people in 43 countries suffer from water scarcity today.


In the United States, most of us are very fortunate to have access to clean water in our homes, just by turning on the tap. The average family of four uses about 400 gallons of water per day. But even taking a five-minute shower can use more water than many others have access to in an entire week. The demand for clean water increases as population growth continues. There are big regional differences in future water availability. While some areas may see more water due to increased precipitation, other areas may have a lot less. For developing countries, climate change may make it even more challenging and costly to provide clean water, as countries have to deal with uncertain weather and changes in local hydrology. For example, glacier melt, altered precipitation, extreme drought and floods, and saltwater intrusion resulting from sea-level rise are all impacts of climate change that threaten global water supply. With current climate change and population growth patterns, about half the world’s population is expected to have some water stress by 2030.



 Clean air

How clean is the air you breathe? We all need clean air to breathe and stay healthy, but if you live in or have visited a big city, then you might know what it is like to breathe in the air next to a busy road – it’s a lot different from breathing in the air from an open meadow. The term air quality is the state of the air around us. Good air quality means that the air is clean, clear and unpolluted. Bad air quality means that there is air pollution. Air pollution comes from unwanted and harmful chemicals in the air. It is a major concern and results from many of today’s modern activities, including driving a car, turning on the air conditioning, and running the large factories that produce power. We’ve learned that pollutants released from industrial activities contribute to greenhouse gases and climate warming, but they can also be bad for our health. Pollutants in the air can irritate our eyes and nose, and even lead to trouble breathing. Asthma has been linked to increased exposure to air pollution.



Coal plants are one of the worst air polluters. Burning coal causes smog, acid rain and toxic air pollution. Sulfur dioxide emitted from a coal plant leads to acid rain that can damage crops and pollute forests, soils, lakes and streams. Nitrogen oxides released lead to ground ozone and smog which
leads to respiratory problems. Mercury also comes from coal plants, which is a major toxin that impacts human health. Many harmful pollutants comes from coal plants. It¹s best for everyone to decrease coal use and use clean energy to help clean up our air!


Ozone (O3) occurs in two layers of our atmosphere, up high and down low. The upper level, about 12 to 19 miles up in the air, is called the ozone layer and it acts as a protective layer from the sun’s powerful rays. Ground-level ozone is created by a chemical reaction between harmful emissions such as nitrogen oxides (NOx) and volatile organic compounds (VOC). These emissions come from places like industrial facilities, chemical solvents, electric utilities, motor vehicle exhaust and gasoline vapors. Ground-level ozone levels can be especially high on a warm sunny day, as the heat of the sun bakes these pollutants. Breathing ozone is bad for our lungs! 

There are many different kinds of pollutants in the air. Some are made as by-products of human activities, and others are natural. Some are categorized as short-lived pollutants, meaning that they don’t stay in the air for very long, but they are nonetheless harmful. Short-lived climate pollutants include methane, black carbon, ground level ozone, and HFCs or hydrofluorocarbons. They exist in smaller quantities than carbon dioxide, but have a much greater warming potential. For example, methane is a gas that comes from animals, like cattle, digesting food. Our landfills also release methane. Methane stays in the air for about 12 years, but traps 20 times more heat than carbon dioxide. Other natural sources of air pollution include dust, ash from volcanoes, and smoke and carbon monoxide from wildfires.

Anthropogenic (human-caused) sources of air pollutants include smokestacks from power plants and fuel-burning machines, like motor vehicles and airplanes. Humans also release pollutants into the air in the form of fumes (like paint and aerosol sprays) and chemicals. As we learned in chapter 2, burning fossil fuels and biomass produces black carbon, sometimes called soot, which has a much stronger warming effect (460 to 1,500 times stronger) than carbon dioxide. If you remember, there is also that gunk, or cryoconite, which gets deposited on glaciers and speeds up melting. HFCs are man-made greenhouse gases that come from air conditioning, refrigeration, and aerosols. Ozone is a by-product of burning fossil fuels, and when inhaled it can be harmful to our lungs.

During the Industrial Revolution, the air pollution was worse than it is today because coal was being burned a lot more to heat homes and used in factories. Smog, which is smoke and fog mixed together, is a kind of air pollution. Smog was a huge problem particularly in London, where the air is humid and there was lots of coal burning. Many laws were passed to help clean up the air and reduce many of the illnesses caused by unclean air. Millions of people around the world today still get sick from unclean air.

Over the past several decades, the United States has done a great deal in helping to clean up our air. You may have heard of the Clean Air Act, which originally passed in 1970 and then was revised in 1990. This environmental action has resulted in dramatic reductions of air pollution and the implementation of new technologies for vehicles and factories that help keep the air cleaner. Because of the Clean Air Act, Americans breathe less pollution, and there are fewer serious health effects.

In another recent effort, the United Nations launched an international initiative in 2012 to reduce the amount of short-lived climate pollutants and promote clean air. The Climate and Clean Air Coalition includes over 34 countries that support finding solutions to reducing these pollutants around the world.

We can make a big difference in cleaning up our air. One of NASA’s satellites, Aura, has been monitoring the air we breathe for the past ten years. And there’s good news: nitrogen dioxide pollution, which is a yellow-brown gas, has decreased! This gas comes from vehicles and power plants and hurts human health, particularly when we breathe in the contaminated air. Check out the video below to see this shift to cleaner air.

What has led to the decrease in air pollution? Mostly technology and policy changes have helped to reduce emissions. The Environmental Protection Agency says that 142 million Americans live in areas with unhealthy air. Many of these are the big cities on the East Coast. But this drop in nitrogen dioxide pollution shows that changes can be made, even with continued population growth, and that we can still do things to help make the air cleaner.


 What’s up with the bugs?

5_6_image_01.jpgClimate change is having a big impact by changing habitats for bugs, some of which carry diseases. Insects that carry a disease and can give it to another organism, typically through biting, are called a vector. Mosquitoes, for example, are a known vector of diseases such as malaria, yellow fever, and dengue fever.

Some insects can survive longer and in new places with warming temperatures. Two diseases that are on the rise are malaria and dengue fever. Malaria is the most lethal, and dengue is the fastest-growing, according to the World Health Organization. With climate change, changes in temperature and rainfall let mosquitoes thrive in new areas, often for longer periods of time. This increases the risk of people being exposed to any diseases that these insects may be carrying.

Have you ever seen a tick? These small little bloodsuckers are found on deer, and sometimes they can land on humans and bite them too. Unfortunately, some ticks carry Lyme disease, which is not a good thing. Studies find that the range of the black-legged tick is expanding northward into Canada as the temperatures warm. The National Wildlife Federation also warns that the milder winters may increase their population by 68% in North America this century. It’s a good idea to double-check for any bites after you have been out in the woods!

Another vector that is being influenced by changes in the climate is the flea, which can carry the plague. Rodents often have fleas, and some are carriers of the plague. If such a rodent bites a human or other animal, then the disease can be spread. You may have heard of the Black Plague, which struck Europe in the fourteenth century, making millions of people very sick. Although that sounds like a scary event from a very long time ago, the plague is still around in some places, and it is expected to spread with shifts in precipitation and temperature.



5_7_image_01.jpgWe know that climate change has major impacts on everything in our lives, from the food we eat to the air we breathe to the places we live. We also know that we need to prepare ourselves for new challenges, like extreme temperatures and extreme events, which are increasing as a result of a changing climate. Some places are getting more rain or seeing more storms, while other places are getting a lot less rain, causing droughts and fires. No one is immune to climate change, as all of our ecosystems are interlinked.

Scientists are actively studying the linkages between extreme weather and abrupt climate change. We need to prepare ourselves for an increase in the intensity and frequency of extreme events, along with making changes to adapt to the already serious impacts of climate change. But don’t give up yet — there are plenty of things that each of us can do to help reduce climate change. In the next chapter, we’ll learn about some exciting things that people are already doing to make a healthier planet for all of us.


  In the Backyard of EIS: Floods,
  Fires and Drought in Colorado

5_8_globe_colorado.pngThe backyard of the Extreme Ice Survey is the Rocky Mountains of Colorado. Headquarters, where EIS processes all the photographs and imagery, is in Boulder, Colorado, which is nestled in the foothills at an elevation of 5,430 feet. The beautiful and majestic Rockies are not immune to the impacts of climate change, and unfortunately, EIS and fellow Coloradans have witnessed some pretty extreme events in the past few years, including major flooding and fires.

In September of 2013, Colorado saw one of the worst floods in the state’s history. Boulder received more rainfall in a three-day period than it had in any month on record. Thousands of people were forced to evacuate, power was cut for days, and many lost their homes and belongings. Flood conditions extended 150 miles across the Front Range of the Rockies. Boulder Creek in downtown crested at 7.78 feet – a record high since 1894.


What was particularly different about this flooding event was that it occurred out-of-season, in September, which is typically one of the driest months of the year. This partly accounts for why the flood was so damaging. When the downpours came, the already dry soil was quickly saturated and it began to flood. The rivers swelled, roads were washed out, and neighborhoods were inundated with water.

Colorado is experiencing a long-term drought, which helps explain why the flooding was so terrible, and why Colorado has experienced so many fires. Drought hardens the soil, which means rainwater runs off the ground more quickly. In addition, due to all the recent fires, there was less vegetation, which usually can help to absorb the rainwater and slow down run-off. The Boulder area in particular was struck with big fires in 2010 with the Fourmile Canyon Fire, and again in 2012, with the Flagstaff Fire. Other parts of Colorado have seen recent record fires too, such as the High Park Fire in Fort Collins in 2012, and the Waldo Canyon Fire a few weeks later in Colorado Springs. In 2013, Colorado saw its worst fire on record, in terms of the number of homes lost (509), the Black Forest Fire.

Scientists are warning that the frequency and intensity of extreme events such as wildfires, droughts and floods are partly related to climate warming. While these kind of events have certainly occurred in the past, some of the recent events partly reflect the compounding effects of climate warming.

These events are really hard to take in when they happen in your own backyard. Our thoughts go out to all families around the world that have had to face these kinds of extreme events. When they happen, be sure to lend your hand to help rebuild our communities.