Betty J Dabney, Ph.D.
The primary effect of the increasing CO2 levels is increasing global temperature in different media as discussed above. Scientists most commonly use surface air temperature and surface ocean temperature, however. The surface ocean temperature is discussed under “Water”.
With respect to surface air temperature, 2015 is on track to be the hottest year on record. Thirteen of the past fifteen years were each the hottest on record at the time according to Climate Central, and the odds of that happening randomly without the influence of Climate Change were 1 in 27 million (www.climatecentral.org, accessed 20 August 2015).
Disequilibrium at a global scale produced by increasing temperature also causes disequilibrium with respect to air currents. In addition, there is more thermal energy in the oceans and air. More water can evaporate, and the warmer air can hold more water. Hence one can expect storms, hurricanes and typhoons, tornadoes, and acute weather events such as rain, hail and snow to be more intense and more frequent. Already we are seeing an increase in severe tornadoes in the US, and the winter of 2014-2015 saw record-breaking snowfall in the Northeastern US. As of August 2015 two major typhoons have threatened Taiwan this year, and recently for the first time there were three typhoons present in the Pacific Ocean simultaneously.
Thus we can say with some confidence that there will be increasing loss of life and property from major weather events. Many of the major cities are located in coastal areas and would be especially vulnerable to hurricanes and typhoons (See section on Water below).
In addition to these acute weather events, Global Warming can cause higher levels of ozone pollution. The formation of ozone from nitrogen oxides and particulates is temperature-dependent; hence we can expect more episodes of unhealthy levels of smog as the average air temperature rises. In some areas of India and China, the air pollution is already lifethreatening. Approximately 4,000 people die every day in China from its air pollution according to one recent estimate by Robert Rohde at the University of California Berkeley. In countries that have air pollution standards for different pollutants, ozone is the most frequently exceeded. Ozone is a severe respiratory irritant and can make heart disease, asthma and other chronic respiratory diseases worse. Whether or not it can cause these conditions is an open question. Ozone can occur in pockets that travel large distances. Some of the ozone pollution has traveled across the Pacific Ocean from China to the US.
High temperatures combined with drought and wind greatly increase the risk of fire. Climate Catastrophe is bringing more fires of larger size and intensity. “Mega-fires”, such as the ones in Greece in the summer of 2007, are too large to be controlled by current fire-fighting resources.
As with the acute weather events described above, one can predict greater loss of life and property from fire as a result of Climate Catastrophe. Normally fire can have a cleansing effect, but vegetation already weakened by prior environmental insults would be less viable and would have more difficulty recovering from fire. Hence we predict the damage from fires will be more extensive and longer-lasting with Climate Catastrophe. Mega-fires may be so extensive that they reduce the availability of wood for lumber, paper and other wood products.
The amount of water on earth is constant. By far the vast majority of earth’s water is sea water. Only 3% is fresh water, but most of this (68%) has been tied up in polar ice. Another 30% of the fresh water is in underground aquifers. The remainder, only about 0.3% of the fresh water (or 0.009% of the total water), is available as surface water for consumption. Figure 4 shows these relationships.
All the water on earth is inter-connected through the Hydrologic Cycle shown in a simplified diagram in Figure 5. Precipitation in the form of rain or snow falls to the surface and will ultimately run off into lakes, streams and rivers through their respective watersheds. As the earth warms snow and ice melt, producing further runoff. Surface water eventually flows to estuaries and oceans to merge with sea water. The salinity of oceans has been constant because the hydrologic cycle has been in equilibrium. However, warming temperatures are changing this equilibrium to favor melting of polar ice, runoff of glaciers, and dilution of sea water.
Climate catastrophe is already producing many effects on both fresh and salt water at a global scale. Changes in weather and climate patterns are occurring with increasing ocean temperatures. While some areas are experiencing more frequent storms, others suffer from severe drought. The El Niño/Southern Oscillation (ENSO) of surface temperatures in the equatorial Pacific Ocean will become more intense. Indeed, the El Niño occurring now in 2015 may be the most intense on record. El Niño can produce excess rain in some areas of the world and deficiencies of rain in others. Figure 6 shows the predicted pattern of El Niño for September – November 2015, visible as the intense red equatorial band in the Pacific Ocean. Some parts of El Niño are predicted to warm by as much as 3o C this year.
With such an active El Niño, some areas will experience a major excess of rain. California, which was in danger of running out of water earlier in 2015, is predicted to have floods and landslides this autumn and winter. El Niño will exacerbate the extremes of acute weather events from Climate Catastrophe, and Climate Catastrophe will exacerbate El Niño. El Niño oscillates with La Niña, where the Pacific Equatorial region is cooler than the surrounding ocean. With Climate Catastrophe we can expect to see more frequent and stronger El Niños and less frequent and/or milder La Niñas.
One of the main effects of Climate Catastrophe is the rise in sea level. This is due to two causes: melting of polar ice and expansion of the volume of the sea water with warming.
The sea level is rising ten times faster than previously thought. According to NOAA and shown in Figure 7, it has risen on average two inches since 1993. Dr. James Hansen, formerly the chief scientist at NASA, believes sea level may rise as much as several meters in the next 50 years because of melting Arctic ice (Hansen et al, 2015). This will be a crisis for the major coastal cities, who must decide how to deal with it.
According to the United Nations Oceans Atlas, approximately 44 percent of the world’s populationlives within 150 kilometers of the sea coast (www.oceansatlas.org) and 40 percent lives within 100 kilometers (http://sedac.ciesin.columbia.edu/es/papers/Coastal_Zone_Pop_Method.pdf)
Readers of this Journal will be especially interested to know that most of Singapore is at an elevation of 15 meters or less (49 feet). In Kuala Lumpur the average is 21.95 m (72.0 ft). While Taiwan is very mountainous, 90 percent of the population lives at 15 meters or lower in the gently sloping western plain. It is not unrealistic that sea level may impinge on these locations in the next two generations. Much of the populated areas of Singapore, Kuala Lumpur, and Taiwan will be under water.
Interestingly, the sea level is not rising at the same rate uniformly all over the earth. Figure 8 shows the deviation in sea level as of 2013. The highest levels were at Taiwan, Singapore, Malaysia and the Philippines. This deviation may itself vary with time, and whether or not these locations will remain the most elevated is to be determined. It is due to complex factors including interaction of ocean currents with land masses as well as local variations in ocean temperatures. The rapid rise in sea level could be devastating for those locations with the largest deviation and where the population is concentrated near the coast.
Another important effect on water from Climate Catastrophe is the acidification of the oceans. Carbon dioxide can react with water to form carbonic acid. Higher concentrations of atmospheric CO2 are causing higher concentrations of carbonic acid to form in the oceans. Although it is a weak acid, it is strong enough to dissolve the calciferous exoskeletons of many marine organisms including coral. Thus we are witnessing the death of the Great Barrier Reef, one of the natural wonders of the earth.
Equally important is the effect on some benthics. Benthics are a family of small microscopic animals that are at the bottom of the marine food chain. Destruction of benthics would affect all marine animal life, from the smallest fish to the great whales. This could create a critical shortage of seafood, which comprises an important part of the diet of people living in coastal areas.
The effects of Climate Catastrophe on water are not limited to the oceans. Rivers are drying up all over the world, a result of less glacial and rain runoff in their watersheds combined with high rates of withdrawal for various uses. Some areas are already being affected in their ability to irrigate crops with river water, notably rice farming. Rice is a dietary staple for billions of people in the world whose lack would have far-reaching implications. According to the National Geographic Society, rivers which are already suffering major impacts are the Colorado in the US, Indus in Pakistan, Amu Darya in Central Asia, Syr Darya in Kyrgyzstan and Uzbekistan, Rio Grande in US and Mexico, the Yellow River in China, the Teesta in Sikkim, and the Murray in Australia. Many of these rivers are a lifeline in their countries.