Climate Change: Why aren't more people concerned about it?

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Malemute

Ice climber
great white north
Jan 5, 2018 - 04:37pm PT
Climate Change Is Suffocating Large Parts of the Ocean

https://news.nationalgeographic.com/2018/01/climate-change-suffocating-low-oxygen-zones-ocean/

http://science.sciencemag.org/content/359/6371/eaam7240
EdwardT

Trad climber
Retired
Jan 5, 2018 - 07:31pm PT
Not sure how rising plant fuel is causing deoxigenation. Seems like a bit of a stretch.
Pet alarmist theory of the month?
Ed Hartouni

Trad climber
Livermore, CA
Jan 5, 2018 - 08:12pm PT
from the Science article:

Causes of oxygen decline
Global warming as a cause of oxygen loss in the open ocean

The discovery of widespread oxygen loss in the open ocean during the past 50 years depended on repeated hydrographic observations that revealed oxygen declines at locations ranging from the northeast Pacific (29) and northern Atlantic (30) to tropical oceans (2). Greenhouse gas–driven global warming is the likely ultimate cause of this ongoing deoxygenation in many parts of the open ocean (31). For the upper ocean over the period 1958–2015, oxygen and heat content are highly correlated with sharp increases in both deoxygenation and ocean heat content, beginning in the mid-1980s (32).

Ocean warming reduces the solubility of oxygen. Decreasing solubility is estimated to account for ~15% of current total global oxygen loss and [greater than] 50% of the oxygen loss in the upper 1000 m of the ocean (9, 33). Warming also raises metabolic rates, thus accelerating the rate of oxygen consumption. Therefore, decomposition of sinking particles occurs faster, and remineralization of these particles is shifted toward shallower depths (34), resulting in a spatial redistribution but not necessarily a change in the magnitude of oxygen loss.

Intensified stratification may account for the remaining 85% of global ocean oxygen loss by reducing ventilation—the transport of oxygen into the ocean interior—and by affecting the supply of nutrients controlling production of organic matter and its subsequent sinking out of the surface ocean. Warming exerts a direct influence on thermal stratification and indirectly enhances salinity-driven stratification through its effects on ice melt and precipitation. Increased stratification alters the mainly wind-driven circulation in the upper few hundred meters of the ocean and slows the deep overturning circulation (9). Reduced ventilation, which may also be influenced by decadal to multidecadal oscillations in atmospheric forcing patterns (35), has strong subsurface manifestations at relatively shallow ocean depths (100 to 300 m) in the low- to mid-latitude oceans and less pronounced signatures down to a few thousand meters at high latitudes. Oxygen declines closer to shore have also been found in some systems, including the California Current and lower Saint Lawrence Estuary, where the relative strength of various currents have changed and remineralization has increased (36, 37).

There is general agreement between numerical models and observations about the total amount of oxygen loss in the surface ocean (38). There is also consensus that direct solubility effects do not explain the majority of oceanic oxygen decline (31). However, numerical models consistently simulate a decline in the total global ocean oxygen inventory equal to only about half that of the most recent observation-based estimate and also predict different spatial patterns of oxygen decline or, in some cases, increase (9, 31, 39). These discrepancies are most marked in the tropical thermocline (40). This is problematic for predictions of future deoxygenation, as these regions host large open-ocean OMZs [oxygen-minimum zones], where a further decline in oxygen levels could have large impacts on ecosystems and biogeochemistry (Fig. 2A). It is also unclear how much ocean oxygen decline can be attributed to alterations in ventilation versus respiration. Mechanisms other than greenhouse gas–driven global warming may be at play in the observed ocean oxygen decline that are not well represented in current ocean models. For example, internal oscillations in the climate system, such as the Pacific Decadal Oscillation, affect ventilation processes and, eventually, oxygen distributions (35).

Models predict that warming will strengthen winds that favor upwelling and the resulting transport of deeper waters onto upper slope and shelf environments in some coastal areas (41, 42), especially at high latitudes within upwelling systems that form along the eastern boundary of ocean basins (43). The predicted magnitude and direction of change is not uniform, however, either within individual large upwelling systems or among different systems. Upwelling in the southern Humboldt, southern Benguela, and northern Canary Eastern Boundary upwelling systems is predicted to increase in both duration and intensity by the end of the 21st century (43). Where the oxygen content of subsurface source waters declines, upwelling introduces water to the shelf that is both lower in oxygen and higher in CO₂. Along the central Oregon coast of the United States in 2006, for example, anoxic waters upwelled to depths of [less than] 50 m within 2 km of shore, persisted for 4 months, and resulted in large-scale mortality of benthic macro-invertebrates (11). There are no prior records of such severe oxygen depletion over the continental shelf or within the OMZ in this area (11).

Nutrient enrichment of coastal waters

Sewage discharges have been known to deplete oxygen concentrations in estuaries since at least the late 1800s (44), and by the mid 1900s the link to agricultural fertilizer runoff was discussed (45). Nevertheless, the number and severity of hypoxic sites has continued to increase (Fig. 2B). The human population has nearly tripled since 1950 (46). Agricultural production has greatly increased to feed this growing population and meet demands for increased consumption of animal protein, resulting in a 10-fold increase in global fertilizer use over the same period (47). Nitrogen discharges from rivers to coastal waters increased by 43% in just 30 years from 1970 to 2000 (48), with more than three times as much nitrogen derived from agriculture as from sewage (49).

Eutrophication occurs when nutrients (primarily N and P) and biomass from human waste and agriculture, as well as N deposition from fossil fuel combustion, stimulate the growth of algae and increase algal biomass. The enhanced primary and secondary production in surface waters increases the delivery rate of degradable organic matter to bottom waters where microbial decomposition by aerobic respiration consumes oxygen. Once oxygen levels are low, behavioral and biogeochemical feedbacks can hinder a return to higher-oxygen conditions (50). For example, burrowing invertebrates that introduce oxygen to sediments die or fail to recruit, and sediment phosphorus is released, fueling additional biological production in the water column and eventual increased oxygen consumption.

Coastal systems vary substantially in their susceptibility to developing low oxygen concentrations. Low rates of vertical exchange within the water column reduce rates of oxygen resupply (51), and long water-retention times favor the accumulation of phytoplankton biomass (14) and its eventual subsurface degradation. Chesapeake Bay develops hypoxia and anoxia that persist for several months during late spring through early autumn and cover up to 30% of the system area. In contrast, the nearby Delaware Bay, which has weaker stratification and a shorter retention time, does not develop hypoxia, in spite of similar nutrient loads (52). Manila Bay is adjacent to a megacity and also receives similar loads on an annual basis, but it becomes hypoxic principally during the wet southwest monsoon period, when rainfall increases nutrient loads and stratification (53).

Low oxygen in coastal waters and semi-enclosed seas can persist for minutes to thousands of years and may extend over spatial scales ranging from less than one to many thousands of square kilometers. Both local and remote drivers lead to temporal and spatial variations in hypoxia. Local weather can influence oxygen depletion in very shallow water through wind mixing and the effect of cloud cover on photosynthesis (54). At larger spatial scales, variations in wind direction and speed (55), precipitation and nutrient loads (56), sea surface temperature (57), and nutrient content of water masses transported into bottom layers of stratified coastal systems contribute to interannual and longer-period variations in hypoxic volume, duration, and rate of deoxygenation (14).

Climate change in coastal waters

Warming is predicted to exacerbate oxygen depletion in many nutrient-enriched coastal systems through mechanisms similar to those of the open ocean: increased intensity and duration of stratification, decreased oxygen solubility, and accelerated respiration (4, 58, 59). The current rate of oxygen decline in coastal areas exceeds that of the open ocean (60), however, likely reflecting the combined effects of increased warming of shallow water and higher concentrations of nutrients. Higher air temperatures can result in earlier onset and longer durations of hypoxia in eutrophic systems through effects on the seasonal timing of stratification and the rate of oxygen decline (58). An ensemble modeling study of the Baltic Sea projects declining oxygen under all but the most aggressive nutrient-reduction plans, owing to increased precipitation and consequent nutrient loads, decreased flux of oxygen from the atmosphere, and increased internal nutrient cycling. Even aggressive nutrient reduction is projected to yield far less benefit under climate change than under current conditions (61).

Because of regional variations in the effects of global warming on precipitation and winds, the rate and direction of change in oxygen content is expected to vary among individual coastal water bodies (4, 58). Where precipitation increases, both stratification and nutrient discharges are expected to increase, with the reverse occurring in regions where precipitation decreases. Changes in seasonal patterns of precipitation and rates of evaporation can also be important. Coastal wetlands that remove nutrients before they reach open water are predicted to be lost as sea levels rise, decreasing capacity to remove excess nitrogen, but the rate of wetland inundation and the ability of wetlands to migrate landward will vary.
Malemute

Ice climber
great white north
Jan 9, 2018 - 09:25pm PT
Malemute

Ice climber
great white north
Jan 10, 2018 - 03:56pm PT
wilbeer

Mountain climber
Terence Wilson greeneck alleghenys,ny,
Jan 11, 2018 - 05:47am PT
Good post up there Ed
WBraun

climber
Jan 11, 2018 - 07:25am PT
The true reality of climate change.

For every action, there is a reaction.

The modern gross physical actions have all been unharmoniously against the true interests of the living self itself.

Modern people are and remain ..... st00pid .....

Reilly

Mountain climber
The Other Monrovia- CA
Jan 12, 2018 - 08:34am PT
I’m officially worried now. A Yellow-bellied Sea Snake was found on the sand at Newport Beach.
Them are some really poisonous little phukkers.
Malemute

Ice climber
great white north
Jan 12, 2018 - 08:48am PT
http://ktla.com/2018/01/11/warming-socal-waters-bring-increased-number-of-rare-venomous-sea-snakes/
Malemute

Ice climber
great white north
Jan 12, 2018 - 09:24am PT
NOAA recaps 2017’s near-biblical collection of weather extremes
https://arstechnica.com/science/2018/01/noaa-weather-events-made-2017-a-year-of-extremes/

Dangerous climate change: Myths and reality
http://www.climatecodered.org/2014/08/dangerous-climate-change-myths-and.html
http://www.climatecodered.org/2014/08/dangerous-climate-change-myths-and_23.html
http://www.climatecodered.org/2014/08/dangerous-climate-change-myths-and_24.html

What would 3 degrees mean?
http://www.climatecodered.org/2010/09/what-would-3-degrees-mean.html

On 6 degrees of climate change
http://www.cnn.com/2015/05/21/opinions/sutter-6-degrees-climate/index.html


Malemute

Ice climber
great white north
Jan 12, 2018 - 09:49am PT
EdwardT

Trad climber
Retired
Jan 12, 2018 - 10:08am PT
Gotta love the NOAA.

Here's their Winter temp forecast.



The temperature outlook shown above indicates above-average temperatures across the southern US, extending northward out West through the central Rockies and all the way up to Maine in the eastern part of the nation.

With that kind of accuracy for the three month outlook, I definitely trust their guestimates for the distant future.
Ed Hartouni

Trad climber
Livermore, CA
Jan 12, 2018 - 10:21am PT
it will be interesting to look at the end of February how the October 2017 prediction fared

keep an eye on this:
https://www.climate.gov/maps-data/data-snapshots/tempoutlook-monthly-cpc-2017-12-31?theme=Temperature
Malemute

Ice climber
great white north
Jan 12, 2018 - 11:27am PT
Importantly, the cooling of our upper atmosphere is further evidence of the human fingerprint on our climate, particularly with respect to global warming. If surface warming were resulting from increasing solar energy, we would actually expect the upper atmosphere to be warming too!

http://www.theclimateconsensus.com/content/satellite-data-show-a-cooling-trend-in-the-upper-atmosphere-so-much-for-global-warming-right
Malemute

Ice climber
great white north
Jan 12, 2018 - 11:45am PT
The Unified Model is a Numerical Weather Prediction and climate modeling software suite originally developed by the United Kingdom Met Office, and now both used and further developed by many weather-forecasting agencies around the world.

https://en.wikipedia.org/wiki/Unified_Model

https://www.metoffice.gov.uk/research/modelling-systems/unified-model

http://journals.ametsoc.org/doi/full/10.1175/BAMS-D-12-00018.1



https://www.nap.edu/read/13430/chapter/16#198
Malemute

Ice climber
great white north
Jan 12, 2018 - 01:15pm PT
Credit: Malemute

https://www.youtube.com/watch?v=N2vWNDNW4BA


moosedrool

climber
Andrzej Citkowicz far away from Poland
Jan 12, 2018 - 05:48pm PT
The real tragedy here is warmer winters in the Lake Tahoe area.

I was hoping to spend the rest of my days in Minden skiing.

Bad, real bad.

Moose
Malemute

Ice climber
great white north
Jan 18, 2018 - 06:27pm PT


This rate of warming is approximately 30 to 50 times faster than the warming that ended the last ice age.

https://robertscribbler.com/2018/01/18/2017-second-hottest-year-on-record-as-climate-troubles-escalate/
Lennox

climber
in the land of the blind
Jan 18, 2018 - 08:31pm PT
This map shows Earth’s average global temperature from 2013 to 2017, as compared to a baseline average from 1951 to 1980, according to an analysis by NASA’s Goddard Institute for Space Studies. Yellows, oranges, and reds show regions warmer than the baseline.

Credits: NASA’s Scientific Visualization Studio





https://www.nasa.gov/press-release/long-term-warming-trend-continued-in-2017-nasa-noaa
Malemute

Ice climber
great white north
Jan 21, 2018 - 08:19am PT
Insurers: Canadian weather getting wetter, hotter and weirder

https://www.ctvnews.ca/sci-tech/insurers-canadian-weather-getting-wetter-hotter-and-weirder-1.3768986
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