My Notes for Climate Change

Sep 2012
358
Panama
#13
Global average temperature for May 2018 was 14C according to this: Global Climate Report - May 2018 | State of the Climate | National Centers for Environmental Information (NCEI) Hot spots are probably more of a worry than the average though. Plenty of data out there if you look ..
There's a lot of confusion here over the difference between a temperature and an "anomaly". A temperature tells us how hot something is. An anomaly can tell us that the global average temperature is a measured amount different from some other measurement or set of measurements --but it doesn't tell us the temperature. A temperature can tell us say, if something is hot enough to melt ice. An anomaly doesn't.

If someone asserts that the global average temperatures for today and in 1760 are 14C and 13C respectively, they have to actually measure temperatures in enough places w/ enough accuracy to come up w/ averages that are believable.

Imagine that someone said that the global average now is 13C and that it was 14C in 1760. They might even present impressive government links, but the rest of us would not believe the temperature numbers if if the links failed to provide the information. Also, we'd be unwilling to even bother searching further merely because someone insisted that it's "out there".
 
May 2018
111
New Zealand
#14
I don't understand why you have a problem with the data being presented as "anomaly" . Temperatures are recorded in multiply locations across the globe. If the average temperature for London in May in the 1800's was 13C and but Paris was 12C , and over the last 10 years London has been 14C but Paris has been 13C , it is much clearer to say that western Europe has increased its average temperature by 1C .... If you follow through the link you'll find some areas have increase much more that 1C for a given month, but others haven't change much. When the data from all the measured locations and months is collated the "average change " or "anomaly" is 1C.
 
Jul 2017
276
Kettering, Ohio USA
#15
Unit 4 - Impacts of climate change

Due to warmer temperatures, mountain glaciers all over the world are receding. The dramatic worldwide shrinking of the glaciers is one of the most visible evidences of global warming. Glaciers act as a kind of global fever thermometer. People and governments in many countries are alarmed.

Melting glaciers pose multiple dangers: Initially, the increasing amount of meltwater can have a positive effect for hydropower. At the same time, emerging glacial lakes have the potential of sudden drainage that could cause devastating floods. In the long-term, severe water shortages can be expected when there will be no or only very little ice left to melt in the summer. The time frame for this to happen varies greatly depending on the geographic location; it may be a matter of just a few years, decades, or, in the case of the Himalayas, several centuries.

Most worrisome is that the polar ice caps began melting as well. The accelerating speed of their melting has even surprised scientists who predicted the thawing. Between the 1960s and the 1990s, sea-ice depth in a large section of the Arctic Ocean declined by nearly 40%. 8 From 1979 to 2005, Arctic sea ice has shrunk roughly 250 million acres (1’011’714km2), an area the size of New York, Georgia, and Texas combined.9 For a European comparison, this is the size of Germany, Italy and Poland combined.

“The most dramatic loss of ice in recent years has been the decline of summer sea ice in the Arctic Ocean. Between 1953 and 2006, the area covered by sea ice in September shrunk by 7.8 percent per decade, more than three times as fast as the average rate simulated by climate models. Researchers were further stunned in the summer of 2007 when Arctic sea ice extent plummeted to the lowest level ever measured, more than 20 percent below the 2005 record. This decline is rapidly changing the geopolitics of the Arctic region, opening the Northwest Passage for the first time in recorded history and triggering a scramble among governments to claim large swaths of the potentially resource-rich Arctic sea floor. Many now believe the summer Arctic Ocean could be ice-free by 2030, decades earlier than previously thought possible.”

On 21 December 2010, large areas of open water persisted across much of the area between Greenland and Canada. While the US Northeast and Europe experienced a cold spell, a vast region in Northern Canada was extremely mild. According to David Phillips, a senior climatologist with Environment Canada, the implications for people have been widespread. “Last New Year’s Eve, the big story was ice breaking up,” says Phillips. “This year there was no ice to break up.” Worst of all, he adds, “it’s impossible for many people in parts of the eastern Arctic to safely get on the ice to hunt much needed food for their families—for the second winter in a row. Never before have we seen weather impact a way of life in so many small and big ways.”11

The Greenland ice sheet is also melting. It holds enough water to raise sea levels worldwide by 6m (almost 20 feet).12 "If greenhouse gas emissions are not controlled, the total disintegration of the Greenland ice sheet could be set in motion in a matter of decades. Although the process could take centuries to fully play out, once begun, it would be self-reinforcing, and hence virtually impossible to stop." 13

Even on the coldest continent, Antarctica, the effects of global warming have set in. The ice on East Antarctica still seems to be stable and has even been growing in recent years. The likely reason for the increase of ice on East Antarctic is more precipitation due to global warming, because a warmer atmosphere can hold more moisture. But scientific research revealed that the temperature over West Antarctica has probably increased by 2°C (3.6°F) since 1950. Measurements on the much smaller Antarctic Peninsula showed temperature increases of up to 3°C (5.4°F).

In July 2017, one of the biggest ever recorded ice shelfs, calved away from the Larsen C Ice Shelf in Antarctica. The broken off iceberg covers 5,800 square km and weighs more than a trillion tonnes.16 The size of the iceberg is larger than the island of Bali in Indonesia and comparable to the state of Delaware or four times the city of London.17 Scientists see the Larsen C collapse as a warning that much larger amounts of ice in West Antarctica could be vulnerable.18

There are two major reasons why sea levels have been rising: 1. When water warms up, its volume increases. This is called thermal expansion. 2. The melting of glaciers adds huge amounts of freshwater to the oceans. The melting North Pole does not contribute to sea level rise because its ice is over water. However, the ice from Greenland and Antarctica, which is over land, is of great concern. “Over the past 100 years, global sea level has risen by between 10 and 25cm (3.9 and 9.8 inches)” in different regions. 21 This range of sea levels results from the regional variations in the geophysical forces and varying ocean currents that determine mean sea level at different places on the Earth’s surface. The rate of global average sea level rise has increased from 1.8mm/yr to 3.1mm/yr from 1961 to 1993. This trend of accelerating sea level rise is expected to continue for many centuries.

“Warming of 4°C (7.2 °F) will likely lead to a sea-level rise of 0.5 to 1 meter (1meter = 3.3 feet), and possibly more, by 2100, with several meters more to be realized in the coming centuries. Limiting warming to 2°C (3.6°F) would likely reduce sea-level rise by about 20 cm by 2100 compared to a 4°C world. However, even if global warming is limited to 2°C, global mean sea level could continue to rise, with some estimates ranging between 1.5 and 4 meters above present-day levels by the year 2300. Sea-level rise would likely be limited to below 2 meters only if warming were kept to well below 1.5°C.” 22

A more recent NOAA report suggests that the current melting rate of alpine glaciers and glaciers in Greenland and Antarctica, as well as the rate of thermal ocean expansion, may cause sea levels globally to rise an average of 0.3 m (about a foot) in the low-consequence/high-probability scenario but up to an average of 2.5 meters (about 9 feet) in its extreme-consequence/low-probability scenario by 2100. 23

Rising sea levels will result in land and habitat loss in many countries. Bangladesh may lose almost 20% of its land area. Hundreds of coastal communities, Small Island States in the Pacific and Indian Oceans and the Caribbean would be inundated, forcing their population to relocate.24 The low-lying island nation of Tuvalu, midway between Hawaii and Australia, is already pursuing plans to evacuate. Some inhabitants of Kiribati have already left their country and resettled in New Zealand and other places. 25 The atoll-based nation of the Maldives is also significantly at risk to disappear into the ocean.

"What would you do if you knew that your country was to disappear in the next two to three decades, and together with your country you would also lose your home, your culture, your way of life? This is what faces the people who live in the four atoll nations in the world - Marshall Islands, Kiribati, and Tuvalu located in the Pacific Ocean, and the Maldive Islands located in the Indian Ocean. These atolls will cease to exist in the next few decades as a result of sea level rise.

“As sea levels are rising because of climate change, the inhabitants of these islands will lose their home. What will happen to their language that describes so well this environment of an atoll, with numerous words describing in detail the various daily and seasonal phases of the ocean tides, or the stages of the development of a new coconut, or the detailed descriptions of the ocean currents, which are used to navigate around the vast expanses of ocean? What will happen to the people, to their way of life, their cohesiveness, their understanding of how to get along in such isolated circumstances? What about their cultures? And finally, what will happen to their enthusiasm for life, their laughter, their amazing generosity, their ways of being all inclusive towards everyone, their gentleness - their 'spirits'?

“Now put yourself in their circumstances: total devastation of your way of life, caused by the actions and life styles of others, and totally out of your control to change or stop this destruction! How does this make you feel? What are the spiritual implications? Where is justice?”

Experts with the United Nations University estimate that rising sea levels and environmental deterioration have already displaced about 50 million people. The greatest cost of rising sea levels will not be measurable. It is the inevitable disruption of communities and cultures that cannot be replicated elsewhere. 27 However, in the not very distant future, that is later on this century and beyond, hundreds of millions of people will become displaced if sea levels will rise a few meters. Many large cities especially in Asia and North America will be flooded such as Guangzhou and Tianjin (China), Mumbai and Kolkata (India), New York, NY, Tampa, FL, and Boston, MA (USA), and Abidjan (Ivory Coast). 28 Many important, historical cities around the world like Venice (Italy), New Orleans USA), and Amsterdam (Netherlands) will be lost to the ocean.

Now, let’s examine some issues of the tangible water beginning with a passage from the United Nations 2018 Report on Water and Sanitation: “Water-related ecosystems and the environment have always provided natural sites for human settlements and civilizations, bringing benefits such as transportation, natural purification, irrigation, flood protection and habitats for biodiversity. However, population growth, agricultural intensification, urbanization, industrial production and pollution, and climate change are beginning to overwhelm and undermine nature’s ability to provide key functions and services. Estimates suggest that if the natural environment continues to be degraded and unsustainable pressures put on global water resources, 45 per cent of the global gross domestic product, 52 per cent of the world’s population and 40 per cent of global grain production will be put at risk by 2050. Poor and marginalized populations will be disproportionately affected, further exacerbating rising inequalities.”

“844 million people still lack even a basic water service. 2.1 billion people lack water accessible on premises, available when needed and free from contamination.”32 Many millions of people face a daily struggle to secure safe water for their basic needs.”

The amount of freshwater is finite while demand is increasing. “One billion people around the world don't have access to clean, safe water. In developing nations, waterborne illnesses like cholera, typhoid and malaria kill 5 million people each year -- 6,000 children every day. And global warming is exacerbating this crisis as severe, prolonged droughts dry up water supplies in arid regions and heavy rains cause sewage overflows.”

In Africa, by 2020, 75 to 250 million people are projected to be exposed to an increase in water stress due to climate change.35

“In Sana’a, the capital of Yemen—home to 2 million people—water tables are falling fast. Tap water is available only once every 4 days; in Taiz, a smaller city to the south, it is once every 20 days.”

“People who fall ill from waterborne diseases can't work. Women and girls who travel hours, sometimes more than seven hours a day, to fetch clean water for their families can't go to school or hold on to a job. Without proper sanitation, human waste pollutes waterways and wildlife habitat. Global warming and population pressures are drying up water supplies and instigating conflict over scarce resources.” 37

In many parts of the world, lakes are shrinking or disappearing and rivers are running dry. Lake Chad, for example, has shrunk by 95% since about 1960. This had disastrous consequences for the local population. The main causes are the diversion of water for irrigation and less rainfall because of climate change. Many large rivers like the Yellow River, the Colorado River or the Nile don't reach the ocean anymore.38

A June 2018 Indian Government Report states “India is suffering from the worst water crisis in its history and millions of lives and livelihoods are under threat. Currently, 600 million Indians face high to extreme water stress.” “About three-fourth of the households in the country do not have drinking water at their premise. With nearly 70% of water being contaminated, India is placed at 120th amongst 122 countries in the water quality index.”39

An extremely serious threat to water supply is the disappearance of glaciers which provide much needed melt water during the summer.40

Ice and snow are huge water reservoirs, which feeds rivers during the summer. 80% of the South American Glaciers could disappear within only 15 years. The consequences for the water supply will be devastating. Lima’s 12 million inhabitants derive their water almost exclusively from the glaciers’ melt water.

It is estimated that 30 million people are at risk of losing their glacial water supply in the Andes due to climate change. The Chacaltaya glacier near La Paz has experienced 99 percent loss since 1940. With glaciers projected to disappear, and no other water sources available, millions of people will be forced to migrate. Ecuador, Peru, and Bolivia are all affected by glacier melting. Conflicts have arisen in urban areas over privatized water, and a greater struggle exists between those seeking water for cities versus those needing resources for agriculture.41

Outside of the polar regions, the Himalayas have the largest concentration of glaciers in the world and their melt water is the major source of water for the Indus and the Ganges rivers. Satellite images have revealed an “alarming recession” of glaciers in the Bhilangna basin of the Garhwal Himalayas since 1965. Its largest glacier, the Khatling, had receded 4,340 meters and had fragmented into multiple valley glaciers. “The alarming retreat and fragmentation of valley glaciers into smaller glaciers may have profound impact on the future sustainability of Himalayan glaciers and water availability.”

The following statement from the IPCC’s 2007 Synthesis report summarizes the vast reaching threat of climate change to water security: “Climate change is expected to exacerbate current stresses on water resources from population growth and economic and land-use change, including urbanisation. On a regional scale, mountain snow pack, glaciers and small ice caps play a crucial role in freshwater availability. Widespread mass losses from glaciers and reductions in snow cover over recent decades are projected to accelerate throughout the 21st century, reducing water availability, hydropower potential, and changing seasonality of flows in regions supplied by meltwater from major mountain ranges (e.g. Hindu-Kush, Himalaya, Andes), where more than one-sixth of the world population currently lives.”

“The link between water and food is strong. We each drink on average nearly 4 liters (about 1 gallon) of water per day in one form or another, while the water required to produce our daily food totals at least 2,000 liters (528 gallons) —500 times as much. This helps explain why 70 percent of all water use is for one purpose—irrigation.”

Aquifers are over-pumped in many countries. “There are two types of aquifers: replenishable and nonreplenishable (or fossil) aquifers. Most of the aquifers in India and the shallow aquifer under the North China Plain are replenishable. When these are depleted, the maximum rate of pumping is automatically reduced to the rate of recharge.

For fossil aquifers, such as the vast U.S. Ogallala aquifer, the deep aquifer under the North China Plain, or the Saudi aquifer, depletion brings pumping to an end. Farmers who lose their irrigation water have the option of returning to lower-yield dry land farming if rainfall permits. In more arid regions, however, such as in the southwestern United States or the Middle East, the loss of irrigation water means the end of agriculture.”

The U.S. embassy in Beijing reports that wheat farmers in some areas are now pumping from a depth of 300 meters (nearly 1,000 feet). Pumping water from this far down raises pumping costs so high that farmers are often forced to abandon irrigation and return to less productive dry land farming.46

“Northern Kenya has become measurably drier and hotter, and scientists are finding the fingerprints of global warming. According to recent research, the region dried faster in the 20th century than at any time over the last 2,000 years. Four severe droughts have walloped the area in the last two decades, a rapid succession that has pushed millions of the world’s poorest to the edge of survival. More than 650,000 children under age 5 across vast stretches of Kenya, Somalia and Ethiopia are severely malnourished.”

Changes in precipitation patterns are observed in many parts of the world. The timing and amount of rain are very important for crops. Farmers need to adapt and learn how to do things differently, for example plant different seeds, or different crops, or plant them at different times of the year.
 
Jul 2017
276
Kettering, Ohio USA
#16
It is important to know the difference between weather and climate:
“Weather is what the forecasters on the TV news predict each day. They tell people about the temperature, cloudiness, humidity, and whether a storm is likely in the next few days. Weather is the mix of events that happens each day in our atmosphere. Climate is the average weather in a place over many years. While the weather can change in just a few hours, climate usually takes hundreds, thousands, even millions of years to change.” 1 Summarized in everyday language one could say “Climate is what you expect; weather is what you get.”

Many regional temperature changes have already been observed: Since 1950, in many regions of the world, records show a decrease in the number of very cold days and nights and an increase in the number of extremely hot days and warm nights. Spring starts earlier in the Northern Hemisphere than it used to a few decades ago.2

Although climate change is a reality all over the globe, the warming is not evenly distributed. At the poles, for example, climate change is occurring at an accelerating pace. In the Arctic, annual average surface air temperature over land is now 3.5°C (6.3°F) warmer than at the beginning of the 20th century.3

The Arctic continues to warm at a rate about twice as fast as the rest of the world. The national Snow & Ice Data Center reported on March 6, 2017, that the “February air temperatures over the Barents Sea ranged between 4 to 5°C (8 to 9° F) above average.”4 Scientists, as well as the indigenous people of the Arctic, have noticed dramatic changes that have affected ecosystems and wildlife, and the way of life of indigenous peoples.

Abnormally severe heat waves are increasing in many parts of the world and are causing much human suffering. In 2013, Australian Forecasters had to add new colors to their temperature charts to adequately show their record heat.6

In early summer 2017, temperatures in Southern Italy exceeded 40°C.7 Pakistan probably suffered the most that summer with temperatures up to 54°C (129.2°F)8

Devastating forest fires claimed more than 60 lives in Portugal in June 20179 and, in Sicily, forced the evacuation by boat of more than 700 tourists.10

Changes in precipitation (rain and snow) are already occurring in many regions of the world. It has become significantly wetter in eastern North and South America, northern Europe and northern and central Asia, but drier in the Sahel, southern Africa, the Mediterranean, and southern Asia. There is less snow and more rainfall in northern regions. Widespread increases in heavy precipitation events have been observed, even in places where the total amount of precipitation has decreased. These changes are associated with increased water vapor in the atmosphere arising from the warming of the world's oceans, especially in the lower latitudes. There are also increases in some regions in the occurrence of both droughts and floods.11 Europe, for example has been suffering from both droughts and floods in the past years.

Even on a warming planet we may still encounter some cold spells and hard winters. With more water vapor in the atmosphere, the occurrence of very heavy snowfalls is also expected to increase.

The severity of extreme weather conditions is increasing. “As sea surface temperatures rise, particularly in the tropics and subtropics, the additional heat radiating into the atmosphere causes more destructive storms.” 12 “The number of Category 4 and 5 hurricanes worldwide has nearly doubled over the past 35 years. The change occurred as global seasurface temperatures have increased over the same period.”

The severity and scope of flooding are steadily increasing. The 2017 flooding of the Gulf Coast by hurricane Harvey was unprecedented. The human suffering and the economic damages are impossible to take in. The flood in South Asia in August 2017 was even worse. More than 1000 people died and at least 41 million people in Bangladesh, India and Nepal have been directly affected by flooding and landslides resulting from the monsoon rains. One third of all of Bangladesh was under water.15 That's an unimaginable catastrophe. In early 2019, hundreds of thousands of cattle died in extensive flooding in Queensland, Australia.16

We shouldn't be surprised though. Scientists have warned that floods will become more frequent and more severe, because of global warming. More moisture evaporates from warmer soils and oceans, and warmer air can hold more moisture. So when it rains (or snows) there is much more water. Another important reason for the worsening floods in coastal areas is sea level rise, which we discussed in Part 1 of this unit.

As the Earth is continuing to warm, such devastating floods and storms will likely become much more frequent and even worse.

"The thin layer of topsoil that covers the planet’s land surface is the foundation of civilization. This soil was formed over long stretches of geological time as new soil formation exceeded the natural rate of erosion. As soil accumulated over the eons, it provided a medium in which plants could grow. In turn, plants protect the soil from erosion. Human activity is disrupting this relationship.

Sometime within the last century, soil erosion began to exceed new soil formation in large areas. The accelerating soil erosion can be seen in the dust bowls that form as vegetation is destroyed and wind erosion soars out of control. Among those that stand out are the Dust Bowl in the U.S. Great Plains during the 1930s, the dust bowls in the Soviet Virgin Lands in the 1960s, the huge one that is forming today in northwest China, and the one taking shape in the Sahelian region of Africa. Each of these is associated with a familiar pattern of overgrazing, deforestation, and agricultural expansion onto marginal land, followed by retrenchment as the soil begins to disappear.

The 2 to 3 billion tons of fine soil particles that leave Africa each year in dust storms are slowly draining the continent of its fertility and, hence, its biological productivity. In addition, dust storms leaving Africa travel westward across the Atlantic, depositing so much dust in the Caribbean that they cloud the water and damage coral reefs there.

Ethiopia, a mountainous country with highly erodible soils on steeply sloping land, is losing an estimated 1 billion tons of topsoil a year, washed away by rain. This is one reason Ethiopia always seems to be on the verge of famine, never able to accumulate enough grain reserves to provide a meaningful measure of food security.”

Climate change will exacerbate soil degradation in many parts of the world. In drier areas, climate change is expected to lead to salinization and desertification of agricultural land. 19

"By 2025, Africa could lose as much as two-thirds of its arable land compared with 1990, and there could be declines of one-third in Asia and one-fifth in South America. Migration – from the Sahelian regions to the West African coast, from sub-Saharan Africa to Europe, from Mexico to the United States – will be an inevitable consequence as poor people are driven off their land." 20 In some countries in Africa, agricultural yields could be reduced by up to 50% by 2020. 21

Higher temperatures take a great toll on agriculture. “More people on the planet depend on rice than on any other crop. Rice plants react very quickly to temperature change: they show a 10 percent drop in yield for every 1ºC (1.8°F) rise in minimum temperature. In parts of the Philippines, farmers have had to stop growing rice completely during the droughts caused by the ‘El Nino’ years, and river delta and coastal rice production has already suffered badly across South-East Asia because of storms that overwhelm sea defenses and salt-water intrusion into paddy fields. An Asian Development Bank report warns that rice production in the Philippines could drop by 50–70 per cent as early as 2020.”

Although higher harvests can be expected in some areas of higher latitude because of milder temperatures and the fertilization effect of more CO2, world wide, agriculture will be severely affected and global food production will decline. And we already have a problem with hunger: “More than 800 million people worldwide suffer from malnutrition. About 24,000 people die every day as a result.” 23 Since 2002, when Kofi Annan made this statement, a global food crisis has started to emerge. There are many reasons for it: The diversion of good agricultural land to grow plants for bio-fuels, environmental degradation of agricultural lands, declining fisheries, and last, but not least, climate change impacts, especially droughts, heat waves, floods and unpredictable changes in precipitation patterns. According to Oxfam International “climate -related hunger could be the defining human tragedy of this century.” 24 Severe droughts are plaguing East Africa. In Somalia alone, “more than 6 million – or around half the total population – are in need of aid.”

“Somalia is one of four countries – including Nigeria, South Sudan and Yemen – for which the UN has launched a US$4 billion appeal to avert famine. But the effects of drought are being felt all across the east coast of Africa – from Ethiopia, where failed rains have affected 80% of the country’s crops, to South Sudan, which has already become the first country in five years to declare an official famine; and from Kenya, which has declared a national emergency, to Zimbabwe and even South Africa.” “The current drought is the region’s severest in decades, but it is far from unprecedented. In fact, climate change is making frequent droughts almost inevitable.” “In pre-1970s Kenya, there was a serious drought around once every ten years. By the 1980s, this had doubled to once every five years. Today, there are droughts almost every other year.” “Kenya’s meteorological office has confirmed the signs of climate change – including measurable changes in the seasons and more sporadic and unpredictable rain, leaving farmers unsure when to plant their crops in order to catch the rains when they do come.”

Forests play a vital role in maintaining the balance of the Earth's ecosystems. They provide habitat for more than half of all terrestrial species, help filter pollutants out of the air and water, and prevent soil erosion. Rainforests also provide essential hydrological (waterrelated) services. For example, they tend to result in higher dry season streamflow and river levels, since forests slow down the rate of water or rain run-off, and help it enter into the aquifer. Without a tree cover, the water tends to run off quickly into the streams and rivers, often taking a lot of topsoil with it. Forests also help the regional climate as they cycle water to the interior of a continent. The shrinking of the Amazon Rainforest reduces regional rainfall, which in turn threatens the health of the remaining forest and of the agricultural land in Southern Brazil. This also results in an increased fire risk.

Forests and their soils also play a critical role in the global carbon cycle. The level of CO2 in the atmosphere depends on the distribution or exchange of carbon between different “carbon pools” as part of the carbon cycle. Forests and their soils are major carbon pools, as are oceans, agricultural soils, other vegetation, and wood products: the carbon stored in the woody part of trees and shrubs (known as “biomass”) and soils is about 50% more than that stored in the atmosphere.

Trees continuously exchange CO2 with the atmosphere. The release of CO2 into the air is due both to natural processes (respiration of trees at night and the decomposition of organic matter) and human processes (removal or destruction of trees). Similarly, CO2 is removed from the atmosphere by the action of photosynthesis, which results in carbon being integrated into the organic molecules used by plants, including the woody biomass of trees. Thus forests play a major role in regulating global temperatures by absorbing heat-trapping carbon dioxide from the atmosphere, and storing it in the form of wood and vegetation – a process referred to as “carbon sequestration”. Unfortunately, the global benefits provided by trees are being threatened by deforestation and forest degradation, a topic we will address in Unit 6.

Forests that have so far escaped deforestation are now threatened by climate change: In many regions of the world, more trees will die because of increasing insect infestations and forest fires. 27 (More insects are surviving milder winters.)

Tropical rainforests, rich in biodiversity, are suffering from warmer temperatures and less rainfall, both caused by climate change. In the past, rainforests were a sink for CO2. Now with hotter temperatures, their growth is impeded, and some are actually emitting CO2.

If climate change is not mitigated, rainforests will not be able to survive. “If the IPCC's most severe projection comes true, much of the Amazon rainforest will transform into savannah.”

Climate change will also have a major impact on Canadian and Manitoba’s forests. Northern latitudes are warming much faster than the global average. In Manitoba, for example, “winters are expected to be 6 – 12°C warmer, whereas summer averages will increase by 2 – 6°C. Such changes will fundamentally alter the growth and range of Manitoba’s forests, affecting wildlife, tourism and forestry. Worst of all, climate change could result in the mass release of terrestrial (stored in the soil and plants) carbon dioxide. Where boreal forests were once sinks that locked down carbon, they may become sources, compounding the effects of climate change.”30

In many parts of the world, wildfires have are becoming more frequent, larger, and more devastating.
“Wildfire risk depends on a number of factors, including temperature, soil moisture, and the presence of trees, shrubs, and other potential fuel. All these factors have strong direct or indirect ties to climate variability and climate change.”31

The dry areas of the world are becoming increasingly drier. There is less precipitation, and the heat dries out the vegetation. The dead brush and dry trees are very flammable. Earlier snowmelt in the spring, caused by warmer temperatures, contributes to dryer conditions in many areas. Lightning storms, which often ignite fires, are also on the increase. The wildfire season has significantly extended, especially in the Western US. “The worst fire years tend to appear amid seasonal extremes, when a wet season that fuels exuberant plant growth is followed by an extremely dry season that sucks the water out of the plants and the soil.

“There’s one other way climate change is influencing the number and frequency of fires, and it has to do with the jet stream, the atmospheric highway high up in the sky that carries weather from west to east. The shape of the jet stream, and how fast weather travels along it, is controlled by the temperature difference between the Arctic and the equator. When the temperature difference is small, weather patterns move more slowly. But climate change is causing the Arctic to warm fast, making that temperature difference smaller. As a result, weather events in the northern hemisphere stay in place for longer. When it’s wet, it stays wet, feeding and plumping plant growth. And when it’s hot, it stays hot, sucking more and more moisture out of those same plants.”

Warmer, drier conditions also contribute to the spread of the mountain pine beetle and other insects that can weaken or kill trees, building up the fuels in a forest.”

Wildfires are also affecting the climate itself. They “emit carbon dioxide and other greenhouse gases that will continue to warm the planet well into the future. They damage forests that would otherwise remove CO2 from the air. And they inject soot and other aerosols into the atmosphere, with complex effects on warming and cooling. A very large, very hot fire destroying 500,000 acres could emit the same total amount to CO2 as six large coal-fired power plants in one year.”

The loss of the diversity of plants and animals is irreversible and long-term. According to the 2014 Living Planet Report by WWF, there was a 52% loss of populations of mammals, birds, reptiles, amphibians, and fish between 1970 and 2010.43 A historical study of over 27 years in Germany showed more that 75% decline in total flying insect biomass. For midsummer population peaks, the drop was 82 percent. “Loss of insects is certain to have adverse effects on ecosystem functioning, as insects play a central role in a variety of processes, including pollination ... and providing a food source for higher trophic levels such as birds, mammals and amphibians. For example, 80% of wild plants are estimated to depend on insects for pollination, while 60% of birds rely on insects as a food source. The ecosystem services provided by wild insects have been estimated at $57 billion annually in the USA.”44

Unfortunately, insects have been disappearing world-wide, not only in Germany. “In the United States, scientists recently found the population of monarch butterflies fell by 90 percent in the last 20 years, a loss of 900 million individuals; the rusty-patched bumblebee, which once lived in 28 states, dropped by 87 percent over the same period.”45

Until now, the major reason for species decline and extinction was the loss of habitat. Now, climate change poses an even greater threat. We can already observe how species are moving towards the poles or up the mountains. In Britain, the comma butterfly, for example, expands its territory northwards, about 80km (50 miles) per decade.46

Many plants and animals cannot move or evolve quickly enough to adjust to the new climate conditions; so they die out. In fact, climate change has already caused the extinction of some species: The Golden Toad, for example, disappeared when reduced precipitation in the Monteverde cloud forests dried out the shallow pools where eggs were laid and tadpoles developed.

“Approximately 20 – 30% of plant and animal species are at increased risk of extinction if increases in the global average temperature exceed 1.5 – 2.5° C (2.7 – 4.5°F).”

Each extinct species is a loss for humanity. We will not be able to use these species for the development of new crops or for the research of new medicines and treatments. Furthermore, species extinctions create holes in the web of life, which disrupt the ecological balance and have far-reaching negative impacts on directly and indirectly connected species. Moreover, each species has intrinsic value that cannot be measured by a one-sided utilitarian approach. Our extermination of our fellow inhabitants of Earth raises strong moral questions.

The ecosystems that are most threatened by climate change are wetlands, mountainous regions, coral reefs, mangroves, and tropical rain forests. In the long term, all ecosystems will be affected by climate change.

Oceans have absorbed at least a quarter of our carbon dioxide emissions. This absorption of CO2 has been very helpful for the climate because it reduced CO2 in the atmosphere and, as a consequence, reduced the warming we have witnessed so far. However, as the gas dissolves in the water it produces carbonic acid. “The acidity of ocean surface waters has increased by 30 percent since the 17th century.” 50 Such a change in ocean chemistry is significant and has long-term effects:

“ Typically, seawater is heavily saturated with dissolved calcium carbonate from eroded limestone. This neutralizes any acid that forms from CO2 and leaves plenty of carbonate for marine creatures to use for shell- and reef-building. But as oceans absorb increasing amounts of CO2 from fossil fuels, their stores of calcium carbonate dip. Over time, this reduces carbonate available for marine creatures. Shell and coral formation slows.” 51 Existing shells can even dissolve. Many ocean creatures depend on calcium carbonate. The most spectacular ones are the corals, which will not be able to survive if the current trend of acidification continues. This problem may have even wider implications, because some zooplanktons are also affected. They are at the basis of the marine food web. This means that many fish and other animals are also threatened by the increasing acidification of the oceans.

There are several direct and many indirect effects of climate change on human health. Most obvious is the threat of heat waves. During the European heat wave in 2003, almost 35,000 people died.52 In Pakistan, people were digging mass graves to prepare for an impending heat wave above 40 degrees Celsius in 2016, because the summer before killed more than 1,300 people, and the fast-decaying corpses couldn't be buried quickly enough.53

Such extreme weather events will become more frequent, prolonged and severe. Vector borne diseases are becoming more widespread because more insects survive the milder winters. Lyme disease is spreading, and so is malaria. Malaria transmitting mosquitoes are multiplying in areas that get more rain and floods, and they are spreading to higher altitudes and latitudes because of warmer temperatures. “It is estimated that climate change has contributed to an average of 150,000 more deaths from disease per year since the 1970s, with over half of those happening in Asia.” 54 Allergy causing ragweed is producing more pollen because of warmer temperature and the fertilization effect of CO2. “The World Health Organization (WHO) estimates that between 2030 and 2050 climate change is expected to cause an additional 250,000 deaths per year due to malaria, malnutrition, diarrhea and heat stress. The direct damage costs to health are estimated at 2 to 4 billion USD per year by 2030, and areas with weak health infrastructures (mostly in developing countries) will be the least able to prepare and respond.”55

Often, a plant, an animal or a whole ecosystem is affected by more than one problem. Let's look at the example of coral reefs: They have been suffering from chemical runoff from agriculture, mainly fertilizers and pesticides. Then marine pollution has been an additional burden. Now with global warming, water temperatures are increasing. Corals are very sensitive to temperature rises. On top of that comes the acidification of the ocean. All these factors combined have contributed to coral bleaching (dying of coral reefs). “Unless significant measures are taken to reduce the stress on coral reefs from human activities, 60% of the world’s coral reefs may die by the year 2050.” 56 Not only plants and animals are affected by a combination of environmental stresses. Unfortunately, people are also suffering from multiple stresses in many parts of the world, for example from the combined disasters of soil erosion, water scarcity and poverty. The Intergovernmental Panel on Climate Change stated, “Africa is one of the most vulnerable continents to climate change because of multiple stresses and low adaptive capacity.” 57

Degradation of freshwaters, decline in food production, energy issues, increase in storm and flood disasters and environmentally induced migration are all potential causes for conflict. 58 “A global population predicted to increase to about 9 billion by the mid-21st century, combined with stresses on water, land, and food resources could create the ‘perfect storm.’” 59 According to a report titled “Insurgency, Terrorism and Organised Crime in a Warming Climate: Analysing the Links Between Climate Change and Non-State Armed Groups,” climate change does not “automatically lead to more fragility and conflict.” Rather, the authors see climate change as a threat multiplier, noting that it “interacts and converges” with other existing risks and pressures in a given context and “can increase the likelihood of fragility or violent conflict.”60 Many countries could face war for scarce land, food and water as global warming increases. More than 60 nations, mainly in the Third World, are likely to have existing tensions exacerbated by the struggle for diminishing resources. Others now at peace - including China, the United States and even parts of Europe - are expected to be plunged into conflict. Even those not directly affected will be threatened by a flood of hundreds of millions of environmental refugees.

In June 2012, before the large increase of refugees trying to get to Europe, the Baha'i inspired International Environment Forum wrote a statement on Preparing for Environmental Migration:

“With accelerating climate change, sea level rise, resource degradation and water shortages, the projected scale of forced environmental migration in coming decades will exceed anything previously experienced, with estimates of 100-500 million people or more permanently displaced. This will be traumatic for those displaced, and represents an enormous challenge for the receiving countries and communities where immigration is presently a major source of political, economic and social tension and human rights violations.”

Massive migrations and shortages of resources have the potential to cause political instability, which may overwhelm many poor countries and result in many more failed states. According to the International Organisation for Migration (IOM), there could be 200 million refugees by the year 2050.

The previously cited statement by the International Environment Forum concludes with a call for the application of ethics: “Faith-based groups should explore the implications of their teachings welcoming guests and strangers. The aim should be to replace the present rejection of immigrants by solidarity with the victims of climate change and other environmental disasters, and a welcoming of displaced persons as new protagonists in building diverse and sustainable communities.”
 
Sep 2012
358
Panama
#17
I don't understand why you have a problem with the data being presented as "anomaly" ....
First: thanks so much for coming back to me on this, it's a long story but your post is important to me. Pse don't get too exasperated, if you feel anger we can come back later, but if you're like me then we can be at a loss together. You're absolutely right, I've completely failed to explain my thinking and I'm at a loss for words.

Maybe this is like something I've been noticing for a long time that tech things are easy --they can be figured out and fixed. The people things are hard ---there's a saying that everyone's entitled to their own opinion but nobody's entitled to his own facts. That's wrong. Everyone's got their own facts because some facts appear to support one opinion and other facts seem to back up the other guy's.

My situation is I believe I'm hearing that that a thing is getting too hot because it's one degree hotter than it was 260 years ago but we have no idea what this thing's temperatures are either for now or for what it was 260 years ago --but just the same we're really sure that it really is 1C hotter and what's more it's too hot now so we've got to spend $trillions immediately or else.

If it were simply a tech prob it would be easy for everyone to just drop it and move on. It's not just technical, it's social and spiritual. I like doing social/spiritual things too but I guess I don't know enough about them to explain how they work.
 
May 2018
111
New Zealand
#18
Getting hung up on the number 1C is the issue, as I mentioned in a earlier post , and is explained by the IPCC the earth isn't warming evenly , there are hotspots.. But most importantly , one cannot ignore the effect of the temperature increase, the polar ice caps are melting, glaciers around the world are receding and coral reefs are bleaching.

Arctic sea ice decline - Wikipedia

Coral bleaching - Wikipedia

These effects of climate change are what are important.

Yes investing in the development of renewable energy sources will cost money, but rising ocean levels and lost ecosystems cost more.


-T
 
Sep 2012
358
Panama
#19
Getting hung up on the number 1C is the issue...
Pls help me understand what's going on here. Are we now saying that the opening statement--
...Since the Industrial Revolution, global average temperature has increased by about 1°C (1.8°F)...
--is no longer considered by this thread to be supported by scientific observation? Are we saying this is valid more precisely in a form of ethereal or mystical reality? Are we saying that rather than being a scientific theory it should more accurately be recieved as a position plank of a progressive/activist movement?

How are we doing this?
 
Sep 2010
4,486
Normanton Far North Queensland
#20
Pls help me understand what's going on here. Are we now saying that the opening statement--

--is no longer considered by this thread to be supported by scientific observation? Are we saying this is valid more precisely in a form of ethereal or mystical reality? Are we saying that rather than being a scientific theory it should more accurately be recieved as a position plank of a progressive/activist movement?

How are we doing this?
Pete its a global average. That would imply some places are cooler, some are hotter?

Regarda Tony
 
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