In one of my previous posts I had posed the
question that this new seemingly extreme weather might be the effects of global
warming. Here are two differing views to help you decide which side you’re on:
“Global warming is making hot days hotter,
rainfall and flooding heavier, hurricanes stronger and droughts more severe.
This intensification of weather and climate
extremes will be the most visible impact of global warming in our everyday
lives. People who have the least ability to cope with these changes--the poor,
very old, very young, or sick--are the most vulnerable.
More weather and climate extremes are likely
to impact U.S. energy security in ways that have not been adequately
considered. For example, major weather-related power outages are already
becoming more common, oil and gas infrastructure in the Gulf region is at risk
as hurricanes and tropical storms intensify, coal transport by rail and barge
across the Midwest and Northeast will face more flooding disruptions, and
electricity generation in the Southwest will be limited by water shortages and
more extreme heat.
Global warming will bring more extreme heat
waves. As the United States warms another 4 to 11°F on average over the next
century, we will have more extremely hot summer days. Every part of the country
will be affected. Urban areas will feel the heat more acutely because asphalt,
concrete and other structures absorb and reradiate heat, causing temperature to
be as much as 10°F higher than nearby rural areas.
Unchecked global warming will worsen
respiratory allergies for approximately 25 million Americans. Springtime
allergies to tree pollens are projected to get worse. In the fall, ragweed is
projected to thrive and become more irritating under increased carbon dioxide
levels. These potential impacts of global warming could have a significant
economic impact: allergies and asthma already cost the United States more than
$32 billion annually in direct health care costs and lost productivity.
Global warming is having a seemingly peculiar
effect on winter weather in the northern United States. Winter is becoming
milder and shorter on average; spring arrives 10 to 14 days earlier than it did
just 20 years ago. But most snowbelt areas are still experiencing extremely
heavy snowstorms. Some places are even expected to
have more heavy snowfall events as storm tracks shift northward and as reduced ice cover on the Great Lakes increases lake-effect snowfalls.
have more heavy snowfall events as storm tracks shift northward and as reduced ice cover on the Great Lakes increases lake-effect snowfalls.
Global warming is shifting precipitation
patterns and also increasing evaporation rates. These trends will create
persistently drier conditions in some places, including the American Southwest.
At the same time, they will intensify the periodic droughts that affect other
regions of the country. These longer and drier droughts will have major
consequences for water supply, agriculture and wildlife. Although the American
Southeast is typically thought of as having abundant water supplies, recent
droughts have served as a wake up call for the region.
Catastrophic wildfires just waiting to
happen. This is the situation now facing the American West. Wildfire frequency,
severity and damages are increasing because of rising temperatures, drying
conditions and more lightning brought by global warming, combined with decades
of fire suppression that allowed unsafe fuel loads to accumulate, a severe bark
beetle infestation that is rapidly decimating trees and ever expanding human
settlements in and near forests.
Global warming has caused more heavy rainfall
events in the United States over the last few decades along with an increased
likelihood of devastating floods. While no single storm or flood can be
attributed directly to global warming, changing climate conditions are at least
partly responsible for past trends. Because warmer air can hold more moisture,
more and heavier precipitation is expected in the years to come. At the same
time, shifts in snowfall patterns, the onset of spring and river-ice melting
may all exacerbate some flooding risks.
Stronger hurricanes, heavier rainfall and
rising sea level: this is what global warming has in store for the U.S. Gulf
and Atlantic coasts. The latest science indicates that maximum hurricane wind
speed will increase 2 to 13 percent and rainfall rates will increase 10 to 31
percent over this century. At the same time, sea-level rise will cause bigger
storm surges and further erode the natural defenses provided by coastal
wetlands that buffer storm impacts.
More and more Americans will be living in
places highly vulnerable to weather and climate extremes as population
continues to grow rapidly in cities, along the coasts and in the South. Racial
and ethnic minorities will be disproportionately impacted because their
populations are concentrated in these places. For example, 56 percent of
African Americans live in the Southern United States or in urban areas.
Furthermore, global warming will add further stress to existing problems in
urban areas, in particular poverty, inequities in access to health care, aging
infrastructure and air pollution.”
This article is thanks to the National Wildlife
Federation.
Now for a differing view on how it’s not the effects
of global warming:
“As part of my exploration of different surface temperature datasets, I’m examining the relationship between average U.S. temperatures and other weather variables in NOAA’s Integrated Surface Hourly (ISH) dataset. (I think I might have mistakenly called it “International” before, instead of “Integrated” Surface Hourly).
Anyway , one of the things that popped out of my analysis is related to our record warm March this year (2012). Connecting such an event to “global warming” would require either lazy thinking, jumping to conclusions, or evidence that the warmth was not caused by persistent southerly flow over an unusually large area for that time of year.
The U.S. is a pretty small place (about 2% of the Earth), and so a single high or low pressure area can cover most of the country. For example, if unusually persistent southerly flow sets up all month over most of the country, there will be unusual warmth. In that case we are talking about “weather”, not “climate change”.
Why do I say that? Because one of the basic concepts you learn in meteorology is “mass continuity”. If there is persistent and widespread southerly flow over the U.S., there must be (by mass continuity) the same amount of northerly flow elsewhere at the same latitude.
That means that our unusual warmth is matched by unusual coolness someplace else.
Well, guess what? It turns out that our record warm March was ALSO a record for southerly flow, averaged over the U.S. This is shown in the next plot, which comes from about 250 weather stations distributed across the Lower 48
Weather records are broken on occasion, even without global warming. And here we see evidence that our March warmth was simply a chance fluctuation in weather patterns.
If you claim, “Well, maybe global warming caused the extra southerly flow!”, you then are also claiming (through mass continuity) that global warming ALSO caused extra northerly flow (with below normal temperatures) somewhere else.
And no matter what anyone has told you, global warming cannot cause colder than normal weather. It’s not in the physics. The fact that warming has been greatest in the Arctic means that the equator-to-pole temperature contrast has been reduced, which would mean less storminess and less North-South exchange of air masses — not more.”
This article thanks to Phd Roy W. Spencer.
So How do you feel about the new weather? Do you believe it is the effects of global warming, or just nothing that should be a big deal?
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