HERE ARE MY NOTES ON GLOBAL WARMING COURSE I TOOK Under the Auspices of the World Bank Massive Open Online Course or MOOC

HERE ARE MY NOTES ON GLOBAL WARMING COURSE I TOOK

Under the Auspices of the 

World Bank Massive Open Online Course or MOOC

Warm by 4C if nothing done by 2100

Could reach 4C by 2060s

Global mean warming is 0.8C above pre industrial level

Oceans warmed by .09C Since 1950

And acidifying

Sea levels rose 20cm since pre industrial times and now rising at 3.2cm per decade 

Sea levels could rise from .5 to 1 meter by 2100

Sea level rise could be 15-20% higher in the tropics than global mean. That’s where the Philippines is.

Target keep warming below 2C

CO2 has continued to increase from preindustrial concentration of around 278 ppm to 391ppm in 2012 with rise at 1.8 ppm per year

316 ppm in 1958 to 391 in 2012

CO2 emissions of about 35,000 million MT per year to rise to 41,000 million MT per year in 2020

Russia heat wave of 2010: crop failure of 25%, 55,000 deaths and burned areas of 1 million hectares and $15 B economic losses

2012 drought in US affected 80% of agricultural land

Rising CO2 concentration and ocean acidification

A warming of 4C would correspond to CO2 concentration of above 800 ppm and 150% increase in acidity. Coral reef growth may stop at 450 ppm. At 2.4C warming, CO2 concentration could reach 550 ppm  and coral reefs may start to dissolve. Extinction of coral reef ecosystems  could occur well before 4C is reached. This would be catastrophic for the Philippines since the country is very dependent on the  sea for food.

Rising sea level:

Warming at 4C will likely lead to sea level rise of  0.5 to 1m by 2100

And by1.5 m to 4 m above present levels by 2300

Sea level rise would be kept to below 2 meters if warming kept to below 1.5C

Cities highly vulnerable to rising sea levels are to be found in Mozambique, Madagascar, Mexico, Venezuela, India, Bangladesh, Indonesia, the Philippines and Vietnam.

Contributors to sea level rise:

1. Thermal expansion of .8mm/yr or .8cm/decade

2. Mountain glaciers and ice caps .7mm/yr or .7cm per decade

3. Ice sheets  .4mm per year or .4cm per decade

4. Negative contribution from dam building and groundwater mining -.1mm per year or -.1cm per decade

Food production:

Global food production would increase for local temperature rise of 1-3C but decrease beyond that temperature

Ecosystems

Risk for disruptions in ecosystems as a result of ecosystem shifts, wildfires, ecosystem transformation and forest dieback would be significantly higher for 4C warming. Could lead to increased mortality & species extinction. In Amazonia, forest fires could double by 2050 with warming of 1.5 to 2C above preindustrial levels. More severe at 4C

Health

Extreme events such as major floods that interfere with food production could also induce nutritional deficits and increased incidence of epidemic diseases. Flooding can introduce contaminants and diseases into healthy water supplies and increase the incidence if diarrheal & respiratory illnesses. May exacerbate under nutrition and malnutrition in many regions - already major contributors to child mortality, with warming of 2 to 2.5C especially in sub Saharan Africa and South Asia, worse at 4C. Changes in temp, precipitation rates and humidity influence vector borne diseases like malaria and dengue as well as hantavirus es, leishmaniasis, Lyme disease and schistomiasis.

Heat

93% goes to the ocean

3% to the ground

3% to ice sheets

1% to atmosphere

Warming waters

Expected to adversely affect fisheries, particularly in tropical regions as stocks migrate away from tropical countries to cooler waters

Ocean hypoxic zone

Layer in the ocean with very low oxygen concentration  called OMZ or Oxygen Minimum Zone, due to stratification of vertical layers ( limited vertical mixing) and high activity of microbes which consume oxygen in processing organic materials deposited from oxygen rich shallower ocean layers with high biological activity. Hypoxic zones globally expand upward with increased ocean surface temperatures, precipitation and/or river runoff, which enhances stratification

Ocean acidification

Oceans play a major role as one of the earth's large CO2 sinks. As atmospheric CO2 rises, the oceans absorb additional CO2. The oceans have taken up approximately 25% of anthropogenic CO2 emissions in the period 2000-06. CO2 reacts with water to form a weak acid resulting in ocean acidification  a decrease of .1OPH calculated from 1750-1994. Acidity observed more pronounced in higher latitudes than tropics . The reaction of CO2 with seawater reduces carbonate ions used for skeleton and shell formation 

Arctic Sea Ice

Reached record minimum in September 2012 since 1973, but could be last 1,500 yrs

Loss of 13% per decade, halving of the ice cover of ice covered area within last 3 decades

Loss of arctic sea ice can cause changes in the dominating air pressure systems.  Since the heat exchange between ocean and atmosphere increase as the ice disappears, large scale wind patterns can change and extreme winters in Europe may become more frequent

Heat waves and extreme temperatures

Exceptional number of extreme heat waves the past decade

European heat wave of 2003

Greek heat wave of 2007

Australian heat wave of 2009

Russian heat wave of 2010

Texas heat wave of 2011

US heat wave of 2012

3 standard deviations or 3 sigma warmer. Without climate change, those 3 sigma events would happen only once in several hundred years.

The five hottest summers in Europe since 1500 happened after 2002. 

Death toll in 2003 in Europe reached 70,000 with daily deaths reaching 2,200 in France. 

Heat wave in Russia killed 55,000 with 11,000 in Moscow, 1 million hectares burned. 

US 2012 63% affected by drought, 7.72 million hectares burned

Drought and aridity trends

Warming of the lower atmosphere strengthens the hydrologic cycle, mainly because warmer air can hold more water vapor. Dry regions become drier and wet regions become wetter. Increased atmospheric water vapor loading can also amplify extreme precipitation, attributed to anthropogenic forcing over Northetn Hemisphere land areas 

Aridity has increased by 1.74% per decade

Agricultural impacts

Maize - each "growing degree day@ spent on temperature exceeding 30C decreases yield by 1 

21st Century projections

Nonmitigation IPCC Special Report on Emissions Scenarios (SRES) Non mitigation warming range for 2100 of 1.6-6.9C above preindustrial temperatures

Best guess climate response, warming projected at 2.3-4.5C, uncertainty being due to how world population, economy and technology will develop during the 21st century

RCP Representative Concentration Pathways

How likely is 4C world

Global mean warming of well over 4C even if all Copenhagen and Cancun pledges are made good, there's still 20% chance of exceeding 4C in 2100

If pledges not made, 40 % chance of exceeding 4 C by 2100 & 10% chance of 4C occurring by 2070s

The most pronounced warming  between 4-10C is likely to occur over land.  Over 10C in the Arctic region. Subtropical region like Med, Northern Africa m, Middle East and US rise of more than 6C

CO2 concentration and ocean acidification 390ppm

pH drop by .1 since preindustrial days equivalent to 30% increase in acidity

4C in 2100 equivalent to 800ppm leading to further pH decrease by another .3 equivalent to 150% acidity increase since preindustrial. Will have very severe consequences for coral reefs, various species of marine calcifying organisms and ocean ecosystems.

If atmospheric COs reaches 450ppm, viral reef growth expected to slow down considerably. At 550ppm reefs are expected to dissolve. CO2 level of below 350ppm required for long term survival of reefs

Droughts and precipitation

Total precipitation on wet days expected to increase by 10%. But extreme precipitation events or 5 wettest days during the year precipitation projected to increase by 20% indicating additional risk of flooding.

The strongest increases of 20-30% during wettest days found for South Asia, Southeast Asia, Western Africa, Eastern Africa, Alaska, Greenland, Northern Europe, Tibet and North Asia. Increases in extreme precipitation concentrated in Northern Hemisphere winter season (December, January and February over Amazon Basin, southern South America, western North America, western North America, central North America, Northern Europe and Central Asia.

Implications for economic growth and human development

The largest increase on poverty due to climate change is likely to occur in Africa, with Bangladesh and Mexico also projected to see substantial climate induced poverty increases 

Predictability of future sea level changes

Greenland and Antarctic ice sheets have large potential contributions to future global sea levels: 7m and 57m respectively 

Sea level rise tends to be larger than the global mean at low latitudes, such as vulnerable locations in the Indian Ocean or in the Western Pacific, and less than the global mean at high latitudes, for example along the Dutch Coast, because of the polar ice sheets and their reduced gravitational pull due to melting. This means the Philippines is in a more dangerous zone.

Changes in extreme temperatures

Prediction: toward the end of the century about every European summer could be as warm as or warmer than the summer of 2003. The european summer of 2003 could be considered cold compared to new climate of 2100.

Agriculture

In relation to the projected effects if climate change, three interrelated factors are important

1. Temperature induced effect

2. Precipitation induced effect

3. CO2 fertilization effect

Changes to levels of precipitation

And water stress in a 2C and 4C world 

In a 2C world, relatively small runoff changes combined with large population growth over next decades mean that changes in water stress would mostly be dominated by population changes, not climate changes

In a 4C world, climate changes would become large enough to dominate changes in water stress in many cases. Water stress expected to increase in Southern Europe, the US, most parts of South America, Africa, australia, while stress expected to decrease in high latitude areas

In 4C, 43 to 50% of global population will be living in water scarce countries compared to 28% today

One major outcome of IPCC studies is that it is primarily the combination of climate change, population change and changes in pattern of demand for water resources that will determine future water stress around the world, rather than climate change alone. This will be further shaped by levels of adaptive capacity

Ecosystem & biodiversity

1. If GHG emissions continue at current rates, the resilience of many ecosystems is likely to be exceeded by an unprecedented combination of change in climate, associated disturbances like flooding, drought, wildfire, insects and ocean acidification plus land use change, pollution and over exploitation of resources

2. Approx 20-30% of plant and animal species are likely to be at increased risk of extinction if increases in global average temperature  exceed 2-3C above preindustrial

3. For increases exceeding 2-3C and in concomitant CO2 concentrations, major changes at

are projected in ecosystem structure and function, species ecological interactions and shifts in species geographical ranges with predominantly negative consequences for biodiversity and ecosystem goods and services such as water and food supply

Humid tropical forests also show increasing risk of major climate induced losses: at 4C, the land extent of humid tropical forest is expected to contract to approximately 25% of original size. At 2C, more than 75% can be preserved.

A decrease in the precipitation over the Amazon forests may therefore result in forest retreat or transition into a low biomass forest.

More than 90% of tropical forests in Amazonia could be preserved at 2C. But just half at 4C

It is the overall diversity if species that ultimately characterizes the biodiversity and evolutionary legacy of life OB earth 

Human health

Undernourishment and malnourishment 

Famine due to crop failure resulting from extreme weather events and changing climate patterns, then increases vulnerability to illness and infection severity. Deaths due to heat wave.

Health impact of extreme events

Amazon rainforest die-back

Tipping point is near 3-5C, collapse of Amazon

Ocean ecosystem

Disruption due to warming and acidification. Lead to demise of most coral reef ecosystems. Expansion of ocean hypoxic zones

West Antarctic Ice Sheet

3m contribution if melts fully

Greenland Ice Sheet

6 to 7m sea level