We All Feel the Increasing Impacts of Global Warming

Summary: All over the world unprecedented weather extremes are occurring, with profound effects on human activities and health.  This post reports some recent climate events.  These instances are consistent with the forecasts that climate scientists have been making for several decades.  The IPCC issued a new, more urgent report in October 2018 specifying that we have to keep the world temperature increase below 1.5°C above pre-industrial levels, primarily by eliminating all emissions worldwide in about two decades.

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Tidal flooding, Eastern U. S.  Many cities along the Eastern seacoast of the U. S. already suffer fair-weather tidal flooding due to rising sea levels.  According to the U. S. National Oceanic and Atmospheric Administration (NOAA) as reported by National Public Radio (NPR), tidal flooding is worsening in more than 40 U. S. coastal cities.  Most of these flood days are not related to storm activity, but rather to rising sea level.  Tides are worst, i.e., highest, when the moon is full or new.  This image

Source: NPR All Things Considered https://www.npr.org/programs/all-things-considered/2019/07/10/740176584

 

shows downtown Annapolis, MD, founded three centuries ago on the shores of Chesapeake Bay, flooded during a high tide in 2017.  As NPR reports, NOAA finds that tidal flooding events in Annapolis have increased by 925% over the last 50 years.  The city is planning a Flood Mitigation Project in conjunction with many agencies including the U. S. Naval Academy, which is located in Annapolis.

Charleston, SC is also suffering from worsening ocean flooding (NPR).  The city is built on a low-lying peninsula, exposed to the sea.  In addition, in recent years flooding has been aggravated by extreme rainfall.  Both of these factors result from worsening global warming.  The city issues flood warnings as frequently as weekly during the summer.  Its officials now understand they must plan for 2-3 feet (0.6-0.9 m) of flooding over the next 50 years.

Temperatures for January-May 2019 for most regions around the globe are warmer than average or set warmest records, whereas only a very few regions were cooler than average (see the following image).

Source: NOAA National Centers for Environmental Information, State of the Climate: Global Climate Report for May 2019, published online June 2019, retrieved on July 10, 2019; https://www.ncdc.noaa.gov/sotc/global/201905 .

The average is for the 30-year reference period from 1981-2010.  It is seen that for the vast majority of global surface pixels the 5-month averages were mildly or much warmer than the 30-year reference period.  In an accompanying graphic NOAA shows land and ocean temperature departures from the 30 year reference period for the January-May interval annually from 1880 to the present (not shown).  Starting about 1976 the departures are all only positive, trending up to 0.8-1.1°C (1.4-2.1°F) above the average between 2015 and 2019.  The full 139-year record shows clearly that, although there are year-to-year variations, the long-term trend in the 5-month global average temperature has been gradually increasing by about 1.3°C (2.3°F) starting at about 1910.

Global warming has been determined to have caused two current climate extremes.  First, a severe heat wave blanketed much of western Europe during the end of June 2019.  It broke heat records across much of the area.  A group of experts in the field of climate attribution examined the temperature data in two ways, as described in a commentary in the journal Nature. 

Attribution science has made great strides in recent years.  In this case, the scientists examined the heat wave in two ways.  First, they compared the actual temperature record with results from climate models for the European region, running cases that included or excluded a man-made greenhouse effect.  They found that the record heat was five times more likely with extra greenhouse gases than without.  Second, they assessed whether historical records going back 100 years are consistent with the actual heat wave data when climate models are used to “hindcast” the data.  They found that global warming and air pollution made the current heat wave 100 times more likely than without those factors. 

More generally, the commentary summarizes that about two-thirds of the 200 attribution inquiries reported to date have positively identified global warming as making the particular event being studied more likely or more severe than without warming.

Second, a report from India describes “Zero Day, the day when a city’s taps dry out and people have to stand in line to collect a daily quota of water.”  This is currently happening in many Indian states because aquifers are being over-drawn and this year’s monsoon rains were 30% less abundant than usual.  The image below exemplifies the disaster:

Women in Rajasthan, India walk long distances to collect drinking water.

Source: Nature India, https://www.natureasia.com/en/nindia/article/10.1038/nindia.2019.84?WT.ec_id=NINDIA-20190710&sap-outbound-id=124373C6B945724353776A88CBC27CF245889A7F&mkt-key=005056B0331B1ED888DF526EE5C22187.

Zero Day has already occurred in the city of Chennai, and is predicted to happen next year in many cities, including the capital, Delhi.  In all 600 million people may be impacted.  Groundwater is the source for most of India’s rural inhabitants and for its agriculture.  The Ministry of Drinking Water and Sanitation states that global warming is one factor contributing to this crisis.

 

Analysis

 

The Paris Agreement of December 2015 pledged 193 members of the United Nations voluntarily to reduce greenhouse gas emission rates sufficiently to keep the planet below a 2°C rise above pre-industrial levels by 2100.  But the Agreement is failing; the rate of emissions is still increasing, raising the total accumulated greenhouse gas burden of the atmosphere.  As a result, the IPCC issued a new, more drastic report in October 2018 specifying that we have to keep that temperature increase below 1.5°C, and to reach a worldwide reduction of emission rates to zero by about 2040, or 21 years from now. 

Failing to achieve this goal will lead to more intense warming, and will contribute to more rapid sea level rise, impacting coastal cities around the world, as discussed above.  It will also contribute to the more intense extremes of heat, such as Europe has experienced, as well as more extreme heat and aridity such as India is experiencing.

The economic harm alone is problematic, since in general our political structures don’t budget for funds to revive the losses, and insurance may be inadequate or nonexistent.  All people of the world have to mobilize individually and politically to eliminate fossil fuel use and develop a renewable energy economy to achieve the goal of zero emissions.

© 2019 Henry Auer

Former Vice President Biden Says Climate Change Is An “Existential” Threat

Former U. S. Vice President Joe Biden spoke before the United States Conference of Mayors on January 24, 2019.  Following the link above takes you to the YouTube video of his address.  Fully half of his 30-minute speech was devoted to the dire need for the U. S. to address climate change rather than retreat from the issue the way the present Trump administration is doing. 

Vice President Biden summarized the important climate and economic benefits generated by the funds in the Obama administration’s Recovery Act of 2009 (intended to stimulate the economy out of the Great Recession) that were directed to mitigating climate change in the U. S.  He then proceeded to offer a heartfelt, sincere and cogent statement on why and how U. S. federal policy should continue to combat climate change by doubling down on policies that reduce greenhouse gas emissions and build a renewable energy economy.  By doing so the U. S. would rejoin all the other nations of the world in our unified campaign to limit further global warming, to which we all subscribed in the Paris Agreement of 2015.

The link above takes one to the video of Biden’s speech.  The portion dealing with climate change begins at about 16 min, 19 sec (16:19) of the video, and continues to about 29 min, near the end.  (For those unfamiliar with YouTube, if you mouse over any part of the video screen the timeline of the video pops up at the bottom of the screen.  Then as the mouse scans along that timeline, you can stop at 16:19 [or any other time you wish].  If you then click on that position the video will begin playing at that point.)

Here are some direct quotes from Biden’s talk, with the time for each statement indicated.

• The Recovery Act included “the single biggest investment in clean energy in the history of the country - $90 billion.  It leveraged $150 billion in the private sector. [It] created hundreds of thousands of clean energy jobs…By the end of the administration there was 30 times as much solar energy and [we were] creating clean energy jobs 12 times faster than any other sector of the economy.” (16:19)
• “There’s no reason that in 2025 all of North America can’t get half of electricity from non-polluting sources.  It’s within our grasp but for special interests!” (20:40)
• Addressing the mayors directly, he said “You also know…it’s a matter of survival.  The threat posed by climate change is existential.” (21:26)
• “You know what the military said [to President Obama and Vice President Biden]?  ‘You know what our greatest security threat is?  Global warming….If sea levels rise…you have tens of millions of people migrating.  That’s how wars start.’” (21:42)
• “Our government’s own most recent report found that heat stress and drought can kill up to a quarter of our corn and soybean harvest.  What’s that going to mean for you mayors from the Midwest…? What does that mean … when John Deere [a major manufacturer of farm equipment] has nothing to plow? (23:40)
• Our scientists have spoken…Since when did we become science deniers?  The United Nations told us…we have 12 years to act before it’s irreversible” (24:07)
• (Referring to the Trump administration intention to pull out of the Paris Agreement)…“you’ve stepped up [addressing the mayors]….400 of you said, no, no, not me….57% of you pledged to take action in 2019”  (25:50)
• “…this is the most urgent priority facing the nation, and we’ll be judged by our children and grandchildren for what we do today.” (27:48)    

  Conclusion

This writer finds it highly significant that Vice President Biden, in his appearance before the United States Conference of Mayors for 2019 devoted so much emphasis to the single issue of climate change.  With all the problems facing our mayors, such as economic and social injustice, and opioid abuse, to name only a few, he chose to stress the importance of the climate change issue as an “existential” threat, stating “this is the most urgent priority facing the nation”.

Skeptics may downplay this speech as being merely a political gesture from someone grappling with the decision of whether to run for president in two years.  Yet there are many other ways he could have addressed our country’s mayors.  Here’s a man who was at the center of national power for eight years.  He came to understand the singular, generational, global significance of man-made emissions of greenhouse gases that have led to intolerable levels of global warming in the short time, geologically speaking, of a figurative blink of an eye.  Mr. Biden is to be praised for this effort.  We all should support his call to action on climate change, regardless of whether he runs for president.

© 2019 Henry Auer

Drought and Extremes of Heat Reduce Farm Yields and Worsen Wildfires

[Updated September 16, 2015]       

Man-made global warming worsens the extreme drought in the American West because of its excessive heating.  Farms in California receive inadequate water supplies, leading to crop losses.  Wildfires are burning record areas of forest in the West as well as in Alaska.  In order to minimize future damaging effects such as these, Americans should join forces with other nations of the world to reduce use of fossil fuels so that greenhouse gas emissions are lowered.

The drought in California.   Barry Baker, an almond farmer in California’s Central Valley, couldn’t provide enough water for the 5,000 acres (about 2,000 hectares) of almond trees he grows, the Vancouver, WA Columbian reported in February 2014 http://www.columbian.com/news/2014/feb/23/drought-drives-california-almond-farmers-to-cut-or/.  So he tore up about one-fifth of his trees, an irreversible decision (see the image below), and had them reduced to wood chips to fuel a local power plant. 

Alan Thompson of G&F Agri Service oversees the removal of almond trees at Baker Farming Company in Firebaugh, CA, on Feb. 3, 2014. (Scott Smith/AP)

Source: The Columbian, Vancouver, WA http://www.columbian.com/news/2014/feb/23/drought-drives-california-almond-farmers-to-cut-or/  

 

The prolonged drought in California, now in its fourth year, has cut supplies of water used to be available to irrigate crops. In July 2015 the state ordered farmers to stop pumping the water.  A year earlier, farmers’ bids for water drawing rights were rumored to be as high as US$3,000 an acre-foot (a measure of water volume), instead of normal rates of about US$60. The wells on California’s farms have been pumping more water out of the region’s aquifer than is replenished by rainfall, so that the land of the Central Valley is actually sinking.  The resulting damage to the aquifer is permanent, reducing its capacity to hold water if and when rainfall returns.

 

Economic effects.  A 2015 study by the University of California, Davis of the economic effects of the drought on agriculture in California projects that a) lack of surface water for irrigation is only partly offset by pumping groundwater from deeper wells at higher cost; b) as many as 21,000 agriculture and related jobs will be lost; c) 542,000 acres (about 217,000 hectares) of agricultural land would lie fallow, more than 25% higher than in 2014; and d) US$2.7 billion of economic activity would be lost.  Thus the drought has serious negative consequences on the state’s economy.

 

Wildfires in the Western U.S.  In the U. S., forest and grassland wildfires have become significant problems in recent years.  So far in 2015, up to August 23, there have been almost 42,000 wildfires which have burned about 7,500,000 acres (about 2,800,000 hectares).  Over the last ten years, information for the year-to-this-date includes some years with higher numbers of fires, but none with a higher acreage burned.  The ten year average for the year-to-this-date was 5,350,800 acres (about 2,140,000 hectares) burned.

 

An example of the damage that wildfires cause is in the image below.

 

House threatened by wildfire in California, about Aug. 2, 2015.

Source: http://us-news.us/firefighter-dies-in-wind-fueled-northern-california-wildfire/

 

 

One firefighter, David Ruhl, 38, died in California on about Aug. 2, 2015 as he was caught in the blaze in the region shown in the photo above.  Three firefighters, Tom Zbyszewski, 20, Andrew Zajac, 26, and Richard Wheeler, 31, died battling a blaze in Washington state.

 

The map below shows the locations of most of the 70 large wildfires active on Aug. 23, 2015.

 

A portion of the U. S. Department of Agriculture, Forest Service map showing large (greater than 100 acres (40 hectares)) wildfire incidents present on August 23, 2015.  70 locations are mapped; red, blue, and gray show level 1, level 2 and other incidents, respectively.  In addition to those shown, the total includes five other incidents in Texas, Oklahoma, Louisiana and South Dakota (not shown in this map portion).  The web page stated that in addition there were 99 new fires on this date.

Source: U. S. Department of Agriculture, Forest Service Active Fire Mapping Program; http://activefiremaps.fs.fed.us/ (accessed August 23, 2015).

 

 

The Forest Service states that on this date there were 72 uncontained large fires and 2 contained fires.  Their locations reflect the severe wildfire hazard presented by severe drought conditions in California and the inland regions of the Pacific Northwest.  The U.S. Drought Monitor showed that as of June 30, 2015 most of California, as well as portions of Nevada and Oregon, experienced extreme or exceptional drought, and other regions of Washington state, Oregon, Idaho and Montana experienced severe drought.  In general regions of drought correlate with incidence of wildfires.

 

Wildfires in Alaska.  More than a month earlier, the U. S. National Oceanic and Atmospheric Administration (NOAA) reported that Alaska has had more than 600 fires, burning millions of acres of forest, the worst on record.  More than 350 structures have been damaged or destroyed.  Alaska had extreme high temperatures in interior regions during spring 2015 with temperatures 30ºF (16.7ºC) higher than typical, and were drier than usual as well. 

 

Extreme heat in the West and Alaska. NOAA reports that extreme heat has been prevalent over California and much of the West for the last three years.  This has worsened the effects of drought conditions in the region, which have lasted as long as six years.  In addition to lack of rainfall, low snowpacks in the mountains have led to reduced streamflow in the region, worsening the dryness of the soil.  The high temperatures paired with moderate to exceptional dryness in the American West and Alaska readily set the stage for ignition and spreading of forest wildfires.

 

Expenses of wildfire management.  The total costs of fire management have risen dramatically, by 60% over the last ten years, to US$2.5 billion.  As of Aug. 20, 2015, direct firefighting expenses have reached US$830 million; in all of 2014 the cost was US$1.2 billion.  Because of funding constraints, the U. S. Forest Service has reduced the proportion of administrative personnel and redirected staffing into firefighting in the field.

 

The role of global warming.  When confronted with climate extremes such as those described here, we may wonder whether global warming plays any role.  Generally drought refers to low rainfall; excess heat from global warming worsens its effects.  A. P. Williams and coworkers conducted detailed analyses of climate-related variables for California from 1901 to 2014; (Geophys. Res. Let. 2015; DOI: 10.1002/2015GL064924).  They found the drought was record-breaking in 2014 and a near-record for the three years 2012-2014.  From rigorous statistical analysis the authors estimate that global warming was responsible for 8-27% of the observed excess drought conditions for 2012-2014, and for 5-18% for 2014 alone.  These findings indicate that although drought conditions may originate from various climatic factors operating cyclically over many years, its full extreme extent is worsened by global warming, producing the record conditions identified by the authors.

 

Robeson analyzed periods of drought in central and southern California as far back as 1200 years ago (Geophys. Res. Let. 2015; DOI: 10.1002/2015GL064593.  The drought experienced in 2014, viewed against the earlier droughts, had a probability of happening of once in 140-180 years.  The three-year drought period 2012-2014 was very severe, having a probability of 1 in 10,000.  The four-year drought over 2012-2015 was unprecedented in the 1200 years examined, and is so severe its probability is beyond estimation using the analysis in the report. 

 

The U. S. Environmental Protection Agency reports, in a post current as of July 15, 2015, that Alaska’s long-term average air temperature has increased 3.4ºF (1.9ºC) over the last 50 years, and that winter temperatures have increased by almost twice as much.  The rate of warming in Alaska is twice as fast as it is for the rest of the U. S.  These trends are due to global warming.  The higher temperatures, coupled with the drought in Alaska’s interior, provide the conditions suitable for starting and spreading forest wildfires.

 

Discussion

 

Images such as the photos shown here speak to us directly, as if we ourselves are experiencing the losses shown.  They are immediate and compelling.

 

California farms provide a significant fraction of the vegetable and fruit crops that Americans consume.  Yet in recent years California has experienced record combined heat-and-drought conditions, which have led to destruction of fruit (here, almond) trees, and to land deliberately being withdrawn from cultivation instead of producing crops.  This ultimately can affect us all by leading to scarcity and/or higher prices for the foods we consume.

 

The increasing extent of forest wildfires in U. S. destroys public and private forest lands, and increasingly threatens homes built in the backcountry.  Protecting those homes from fire is the highest priority of wildfire fighters, leading to loss of life and requiring more expenses paid from our taxes. 

[Update] Valerie Trouet and colleagues published a detailed analysis of precipitation in the Sierra Nevada mountains of eastern California online in Nature Climate Change in September 2015.   They focused on the annual mountain snowfall that on melting provides much of the water resources for the state, going back to 1500 C.E.  They found that the water originating as snowfall in the winter of 2015 was the least for the entire 515 year period examined.  The likelihood of such a low snowpack having occurred in the past is estimated at once in every 3,100 years, which points out the extreme nature of this year’s minimum.  In view of projected worsening of man-made warming in the Sierra Nevada, the authors fear “major future impacts” on the region’s water storage ability.

 

Man-made global warming is a significant factor contributing to the harms and damages exemplified in this post.  In order to minimize the effects of further warming, which will only make droughts, food shortages and forest wildfires worse, we Americans have to join with the people of all nations to reduce the use of fossil fuels so that the further accumulation of carbon dioxide is minimized.  Our policymakers are infused with the same humanity common to  all Americans, and with all inhabitants of our planet.  We must come together to implement meaningful measures to combat the warming of our home, the Earth.

 

© 2015 Henry Auer

Public Attitudes about Extreme Weather and Increased Global Average Temperatures

Summary.  Yale University and George Mason University released their latest survey, Extreme Weather, Climate & Preparedness in the American Mind, concerning attitudes of the American public over long-term world-wide average temperature and extreme weather events, in April, 2012.  A clear majority of the American public finds that unusual weather events have occurred in the preceding year.  By more than 2-to-1, people feel that over the past several years the weather has gotten worse rather than better.  Americans associated the recent extreme weather events with long-term increases in global temperature.  The New York Times reports that other recent surveys have provided similar results.

This survey appears to represent a shift toward greater recognition of the consequences arising from long-term increases in global temperature, compared to earlier recent Yale-George Mason surveys.

We conclude by urging American federal policymakers to recognize this shift in attitudes among the (presumably voting) population of the country.  Our policymakers should enact policies that address long-term global temperature increases and their consequences, as well as develop policies that help the country adapt to changes already under way.
 
Introduction.  Concern about an increase in the long-term world-wide average temperature ascribed largely to release of greenhouse gases by mankind has been expressed by climate scientists for several decades.  Harmful effects on climate, extremes of weather, and human consequences from this temperature increase have also been predicted over the same time scale.  Corresponding degrees of concern among the peoples of the world has varied with time and by nation or region of the world.

In the United States, several survey results have tracked details of the public’s recognition of, and degree of concern over, long-term average temperature increases and their effects.  This post discusses a survey of Americans (Leiserowitz, A., Maibach, E., Roser-Renouf, C., & Hmielowski, J. D. (2012) ExtremeWeather, Climate & Preparedness in the American Mind. Yale University and George Mason University. New Haven, CT: Yale Project on Climate Change Communication.)  that was released April 18, 2011 by the Yale Project on Climate Change Communication and the George Mason University Center for Climate Change Communication.  The survey was conducted the second half of March 2012, interviewing 1,008 people.

Climate and Extreme Weather.  The survey notes that in 2011 the U. S. had 14 serious weather and climate disasters each causing US$1 billion or more in physical damage, more than in any previous year.  Total damage from these events has been evaluated as US$53 billion, not to mention human costs of life and disruption of lives for survivors which are not readily calculable.  Disasters included severe drought and an extended heat wave in Texas and Oklahoma, widespread flooding along the Mississippi River valley, the remnants of Hurricane Irene which brought rain deluges and flooding along the east coast, and numerous damaging tornados.  From January to March 2012 temperatures across the continental portion of the U. S. were 6.0ºF (3.3ºC) higher than normal.

This blog reported on extreme weather events and damage assessments in the U. S. over the preceding ten years in this post , and selectively around the world in this post.

Highlights of the Survey. 
 
More than half of Americans surveyed recognized that, for the preceding year, unusual weather events have occurred (56% for their local area, and 62% elsewhere in the U. S.).

82% personally experienced one or more types of extreme weather in the preceding year; extreme weather includes extreme high winds, extreme rainstorms, extreme heat waves, drought, extreme cold temperatures, extreme snowstorms, tornadoes, floods, hurricanes and wildfires.

More than one-third reported that in the past year they were personally harmed (harm to property, financial status, or physical or mental health) by at least one extreme weather event, and separately, more than one-third reported knowing another person who was harmed.

Americans surveyed stated that over the past several years the weather in the U. S. has become worse rather than better, by 52% to 22%.

About half of those surveyed say that, over the past several decades, the extreme events of heat waves, droughts and very heavy rain storms have become much more common or somewhat more common.  Slightly less than half had the same sense with respect to harm to crops, floods, air quality, forest fires, water quality and transportation.

In the survey group, Americans agree, strongly or somewhat, with the notion  that global warming contributed to the severity of several newsworthy extreme events, including the unusually warm winter of December 2011 and January 2012 (72%), record high summer temperatures in the U.S. in 2011 (70%), the drought in Texas and Oklahoma in 2011 (69%), record snowfall in the U.S. in 2010 and 2011 (61%), the Mississippi River floods in the spring of 2011 (63%), and Hurricane Irene (59%).

Analysis

More than half of Americans recognized that unusual or extreme weather events have occurred in the past year, with five-eighths recognizing that such events occurred broadly nation-wide.  Four-fifths of Americans experienced extreme weather themselves, and one-third suffered personal harm as a result.  Significantly, Americans sense that over the past several decades, extreme weather events have become more frequent.  Depending on the event, roughly two-thirds of Americans sense that global warming has contributed to the severity of extreme weather events that occurred in the year preceding the survey.

These results represent a measurable change from previous survey results.  The same consortium published “GlobalWarming’s Six Americas in May 2011” (Leiserowitz, A., Maibach, E., Roser-Renouf, C., & Smith, N. (2011) Global Warming’s Six Americas in May 2011. Yale University and George Mason University. New Haven, CT: Yale Project on Climate Change Communication) .  In that survey, which was conducted with a different focus than the present one, only 37% of those surveyed were either alarmed or concerned about global warming (on a scale of six categories ranging on the negative side to “dismissive”).  These two categories remained essentially constant back to January 2010, but had been as high as one-half in November 2008.  Only 47% of those surveyed agreed strongly or somewhat that the record snowstorms of the winter of 2010-2011 made them question whether global warming is occurring, and 54% agreed strongly or somewhat that record heat waves in the summer of 2010 in the U. S. strengthened their belief that global warming is occurring.  Although the present survey asked no questions concerning the cause(s) of global warming, the May 2011 survey found that 49% of respondents thought that it is caused mostly or partly by human activities.

The New York Times, reporting on the present survey, noted that other recent survey results also show increased concern by the public about climate change and its effects.  In its report, the New York Times quotes A. Leiserowitz, the lead author of the survey report, as saying “People are starting to connect the dots”.

Weather extremes are one consequence predicted by climate scientists for the effects of an increase in the long-term worldwide average temperature.  The Intergovernmental Panel on Climate Change (IPCC) released a “Summary for Policy Makers of its Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation” [Field, C. B., Barros, V., Stocker, T.F., Qin, D., Dokken, D., Ebi, K.L., Mastrandrea, M. D., Mach, K. J., Plattner, G.-K., Allen, S. K., Tignor, M. and P. M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA on November 18, 2011, just ahead of the then-upcoming Conference of the Parties on climate change to convene in Durban, South Africa.  This blog reported on the special report in this post.

In an earlier tutorial post, we presented a basis for understanding that a rise in long-term global average temperature could worsen extreme events.  Very briefly, this is because warmer air holds more moisture than cooler air.  As moisture passes from the vapor to the condensed state (clouds and fog), it releases heat; and in reverse, as clouds evaporate to water vapor, heat is absorbed from the surrounding air.  These localized exchanges of heat lead to temperature gradients that can make winds more intense, and the higher water content of the air affected means that more moisture can fall as rain or snow.   Furthermore, rigorous climate models predict that certain regions of the earth’s surface will become more arid, leading to drought and possible famine, while other regions will experience more precipitation.

Policy for a regime of increasing global average temperatures

The survey reported in this post, and other recent surveys as well, show that the American public is becoming more attuned to the notion that increasing global average temperatures lead to more, and more severe, extreme weather events.  These events lead to damage and harms, physical, mental and societal, that carry with them significant financial losses, losses that ultimately are borne by the taxpayers of the U. S. 

Nevertheless, policymakers responsible for setting priorities and for implementing programs in the U. S. have steadfastly ignored public sentiment concerning this issue.  The U. S. has not been able to put in place a statutory policy program to address contemporary problems related to increasing global average temperatures, nor to develop alternative energy sources that avoid the release of greenhouse gases into the atmosphere.  As the American public becomes more persuaded that increasing global average temperatures lead to severe weather events and their consequences, such as floods, droughts and shortages of food staples, U. S. policymakers should recognize the significance of these shifts in attitudes among the electorate.  Our elected representatives should act on the imminent dangers posed by increasing global average temperatures in order to mitigate their severity, and to adapt to the resulting changed environment.


© 2012 Henry Auer