Bill Stern – “Weather, Climate and How Climatic Changes Impact Weather”

Bill Stern, aa neighbor of many of us who live at Shady Brook gave an interesting and information, as well as somewhat technical, presnetaiton on Weather, Climate, their relationships and some of the realtiies of climate change.

When Bill was jus t13, he had drams of becoming a meteorologist or astronomer.  The storms in 1960-61 however, pushed him toward the science of weather.  He took his undergraduate at NYU garduating in 1970 and then his Masters at MIT, graduating in 1972.  After graduation, he took a position at Princeton as a Research Meteorologist, NOAA, Geophysical Fluid Dynamics Laboratory (GFDL)  and since then has been intimately involved with atmosphere/ocean research, primarily dealing with experimental weather and climate prediction.  While 2/3 retired be is still involved in this reserach as well as being a Visiting Scientist, University Center for Atmospheric Research (UCAR) and  Adjunct Professor in Rutgers Department of Environmental Science

The following are slides from his presentaiton … although lacking his many insights into the the details underlying the research behind the information.

Weather, Climate and How Climatic Changes Impact Weather

Atmosphere – Weather – Climate

Weather or Climate?

  • The high temperature on Jan 7, 2014 in Princeton was 9°F.
  • Example of weather
  • The normal high temperature for New Brunswick for Jan 7 is 39°F.
  • Example of climate
  • Rain is falling at a rate of 1 in/hr in New York City.
  • Example of weather
  • The normal precipitation for January in New Brunswick is about 3.62 inches.
  • Example of climate

Weather: The condition of the atmosphere at any given time and location.

Climate: Historical record of average daily & seasonal weather events over a long period of time for a region.

Graphical Examples of Weather For a Range of Spatial Scales

Hurricane Sandy at Landfall

 

Heavy snow (~2”/hr) at Shady Brook – 07Feb2021 ~9:11AM

Surface Weather Map of Storm

Upper level Weather Map

 

The Basis for Climate Change and how it might impact Weather Phenomena

  • Greenhouse gases – Increase of temperatures Globally
  • Tropical Cyclones – Rising Sea Surface Temperatures
  • Extratropical Weather – Jet Stream changes; more column water vapor (available moisture)

Composition of Atmosphere Near Earth’s Surface

Permanent Gases   Traave (Variable) Gases  *      
% by Volume in Dry Air   % by Volume in Dry Air     Parts Per Million  
                 
Nitrogen 78.08%   Water Vaopr 0 – 4        
Oxygen 21.00%   Carbon Dioxide 0.0405     405  
Argon 0.930000%   Methane ** 0.00018     1.8  
Neon 0.001800%   Notrous Oxide 0.00003     0.3  
Helium 0.050000%   Ozone 0.000004     0.04  
Hydrogen 0.006000%   Particles (i.e.. Dust) 0.000001     0.01 – 0.15  
Xenon 0.000009%   CFCs 0.00000001     0.0001  
      *  Greenhouse Gases          
             

 

 

Climate Change Mechanisms

  • External Causes
  • Change in incoming radiation
  • Change in composition of the atmosphere
  • Change in Earth’s surface
  • Feedback Processes
  • Water vapor-greenhouse gas feedback (+)
  • Snow-albedo feedback (+)
  • Infrared radiation (-)

Atmospheric Greenhouse Effect

Contribution to Atmospheric Greenhouse Effect

  • 60% – Water Vapor
  • 26% – Carbon Dioxide
  •   7% – Methane
  •   7% – Remaining Greenhouse Gases (i.e. Nigrous Oxide CFCs)

 

 

Climate Change “Footprint”

  • Recent Global Warming: Perspective
  • Since the beginning of the 20th century average global surface temperature has increase 0.8ºC
  • Radiative Forcing Agents
  • Carbon dioxide and other greenhouse gases disrupt radiative equilibrium, forming an increase in temperature
  • Climate Models
  • General circulation models (GCMs) are not perfect but extremely sophisticated and serves as the most reliable current predictive tool.

 

 

Climate Change GCM Predictions

  • Future Global Warming: Projections
  • Double carbon dioxide levels will cause a surface warming of 2-4.5ºC
  • Uncertainties:

n The effect of water and land on rising levels of CO2 n Amount or greenhouse gases n Feedback from Aerosols

  • Question of Clouds

n Clouds reflect radiation and emit infrared radiation, positive and negative feedbacks

 

 

 

 

Climate Change and Changes In Weather

  • Consequences of Global Warming
  • Land areas warm faster
  • Rise in sea level
  • Fertilize plants
  • Land Use Change
  • Desertification
  • Plagues and climate

Climate Change and Precipitation

 

Global Warming and Hurricanes

Climate model simulations do not show statistical significance for an increase in the number of hurricanes. However, there does appear to be a statistically significant increase in the number of strong to extreme hurricanes, primarily associated with an increase in sea surface temperatures.

 

 

Summary of Climate Change Impacts on Weather

  • Tropical Cyclones(TCs):

–  More intense hurricanes – Warmer SSTs -> Greater available energy

–  Perhaps associated with heavier rainfall (lower confidence)

–  More landfalling TCs? (lower confidence)

–  Overall perhaps fewer TCs? (lower confidence)

  • In Extra-tropics :

– Generally more precip in N. Hem. During winter, with a notable exception over the US southwest which becomes dryer, leading to droughts and more wildfire potential

–  Evidence for more frequent episodes of heavy precip

Polar jet may move more poleward and get “wavier”, but no clear evidence yet of more frequent or stronger extra-tropical cyclones. Some modelling studies suggest wetter systems.

– No clear evidence of more severe weather outbreaks, but warmer conditions imply an earlier start to tornado season.

–  Expect longer summer heat waves and shorter winter cold outbreaks.

 

In response to some questions:

  • The so-called solar-flux or changes in the sun's radiation is not a major contributor to the changes in our earth's climate in the short term.
  • Buying land for a long-term investment along certain shorelines (read; New Jersey and Florida in particular) could be a risk due to sea level rise.  although only 1 mm to 1 cm per year now, with the accelerated melting of the Arctic and Greenland ice sheets.  As these massive amounts of ice disappear the newly exposed water and land surfaces will refelct back less of teh sun's rays, thus adding to the increasing global temperatures.
  • Fracking's largest threat to the climate is due to the release of methane, particularly at eh wellhead.
  • The deforestation of the Amazon, one of the earth's greates CO2 sinks will also contribute to the increse of carbon diozide in the atmosphere.

Climate Change References (online)

http://www.climatehotmap.org/global-warmingeffects/

https://watchdocumentaries.com/chasing-ice/

IPCC 5th Assessment Report:  http://ar5-syr.ipcc.ch/

UN Report on Climate Change:  https://www.un.org/en/climatechange/repor ts

 

The Club thanked Bill for his time, informatinve presentaiton and insights on atmospheric phenomenons we witness every day.