2016-12-27. Notorious Ocean Current Is Far Stronger Than Previously Thought.
By Emily Underwood, EoS Earth & Space news, AGU.
2016-02-01. Studying the Heart of El Niño, Where Its Weather Begins. By Henry Fountain, The New York Times.
2015-12-15. NASA Examines Global Impacts of the 2015 El Niño.
By NASA Release 15-235.
2015-06-17. Mysterious Warm Blob in Pacific Wreaking Havoc. By Patrick J. Kiger, D news.
2008 May 1. Next decade 'may see no warming'. By Richard Black, Environment correspondent, BBC News website. The
Earth's temperature may stay roughly the same for a decade, as natural
climate cycles enter a cooling phase, scientists have predicted. A new
computer model developed by German researchers, reported in the journal
Nature, suggests the cooling will counter greenhouse warming. However,
temperatures will again be rising quickly by about 2020, they say.
Other climate scientists have welcomed the research, saying it may help societies plan better for the future.
...The key to the new prediction is the natural cycle of ocean
temperatures called the Atlantic Multidecadal Oscillation (AMO), which
is closely related to the warm currents that bring heat from the tropics
to the shores of Europe.
The cause of the oscillation is not well understood, but the cycle appears to come round about every 60 to 70 years.
..."One message from our study is that in the short term, you can see
changes in the global mean temperature that you might not expect given
the reports of the Intergovernmental Panel on Climate Change (IPCC),"
said Noel Keenlyside from the Leibniz Institute of Marine Sciences at
His group's projection diverges from other computer models only for
about 15-20 years; after that, the curves come back together and
...Modelling of climatic events in the oceans is difficult, simply
because there is relatively little data on some of the key processes,
such as the meridional overturning circulation (MOC) - sometimes
erroneously known as the Gulf Stream - which carries heat northwards in
...Looking forward, the model projects a weakening of the MOC and a
resulting cooling of north Atlantic waters, which will act to keep
temperatures in check around the world, much as the warming and cooling
associated with El Nino and La Nina in the Pacific bring global
2008 Mar 1. HEAVY RAIN FLOODS SOUTH AMERICA. NASA Earth Observatory News. Persistent,
heavier-than-normal rains throughout February and March 2008 triggered
flooding across parts of northern and central South America. La Niña conditions in the Pacific may have caused the unusual rainfall.
2008 April 4. Global temperatures 'to decrease'. By Roger Harrabin, BBC News environment analyst. Excerpt: La Niña
caused some of the coldest temperatures in memory in China. Global
temperatures this year will be lower than in 2007 due to the cooling
effect of the La Niña
current in the Pacific, UN meteorologists have said. The World
Meteorological Organisation's secretary-general, Michel Jarraud, told
the BBC it was likely that La Nina would continue into the summer. This
would mean global temperatures have not risen since 1998, prompting some
to question climate change theory. But experts have also forecast a
record high temperature within five years. 'Variability'
La Niña and El Niño are two great natural Pacific currents whose effects are so huge they resonate round the world. El Niño warms the planet when it happens, La Niña cools it. This year, the Pacific is in the grip of a powerful La Niña.
It has contributed to torrential rains in Australia and to some of the
coldest temperatures in memory in snow-bound parts of China.
Refers to the extensive cooling of the central and eastern Pacific
...Increased sea temperatures on the western side of the Pacific means
the atmosphere has more energy and frequency of heavy rain and
thunderstorms is increased. ....Typically lasts for up to 12 months and
generally less damaging event than the stronger El Niño.
2008 January 10. NASA Observes La Niña: This 'Little Girl' Makes a Big Impression Excerpt:
Cool, wet conditions in the Northwest, frigid weather on the Plains,
and record dry conditions in the Southeast, all signs that La Niña is in
full swing. With winter gearing up, a moderate La Niña is hitting its
peak. And we are just beginning to see the full effects of this
oceanographic phenomenon, as La Niña episodes are typically strongest in
January. A La Niña event occurs when cooler than normal sea surface
temperatures form along the equator in the Pacific Ocean, specifically
in the eastern to central Pacific. The La Niña we are experiencing now
has a significant presence in the eastern part of the ocean. The cooler
water temperatures associated with La Niña are caused by an increase in
easterly sea surface winds. Under normal conditions these winds force
cooler water from below up to the surface of the ocean. When the winds
increase in speed, more cold water from below is forced up, cooling the
ocean surface. "With this La Niña, the sea-surface temperatures are
about two degrees colder than normal in the eastern Pacific and that's a
pretty significant difference," says David Adamec of NASA's Goddard
Space Flight Center, Greenbelt, Md. "I know it doesn't sound like much,
but remember this is water that probably covers an area the size of the
United States. It's like you put this big air conditioner out there -
and the atmosphere is going to feel it." While this "air conditioner"
may be located in the equatorial Pacific Ocean, it has a great influence
on the weather here in the United States and across the globe. ...The
Northwest generally experiences cooler, wetter weather during a La Niña.
On the Great Plains, residents normally see a colder than normal winter
and southeastern states traditionally experience below average
rainfall. ...The increased circulation that brings up cold water from
below also brings up with it nutrients from the deeper waters. These
nutrients feed the organisms at the bottom of the food chain, starting a
reaction that increases life in the ocean. NASA's SeaWiFS satellite
documented this increase in hytoplankton during the last La Niña period
in 1998. La Niña and El Niño episodes tend to occur every three to five
years. La Niñas are often preceded by an El Niño, however this cycle is
not guaranteed. The lengths of La Niña events vary as well. "We need to
watch to see if this La Niña diminishes, because they can last for
2006 September 23. Nature provides "ecosystem services". Earth & Sky Radio Show.
2006 September 19. El Nino mystery solved, monsoon forecasts improved. Earth & Sky Radio Show.
1 December 2005. Alarm
over dramatic weakening of Gulf Stream. Ian
Sample, science correspondent, The Guardian
Excerpt: Slowing of current by a third in
12 years could bring more extreme weather.
Temperatures in Britain likely to drop by
one degree in next decade. The powerful ocean
current that bathes Britain and northern Europe
in warm waters from the tropics has weakened
dramatically in recent years, a consequence
of global warming that could trigger more
severe winters and cooler summers across the
region, scientists warn today. Researchers
on a scientific expedition in the Atlantic
Ocean measured the strength of the current
between Africa and the east coast of America
and found that the circulation has slowed
by 30% since a previous expedition 12 years
ago. The current, which drives the Gulf Stream,
delivers the equivalent of 1m power stations-worth
of energy to northern Europe, propping up
temperatures by 10C in some regions. ... Previous
expeditions to check the current flow in 1957,
1981 and 1992 found only minor changes in
its strength, although a slowing was picked
up in a further expedition in 1998.... If
the current remains as weak as it is, temperatures
in Britain are likely to drop by an average
of 1C in the next decade, according to Harry
Bryden at the National Oceanography Centre
in Southampton who led the study. ...The current
is essentially a huge oceanic conveyor belt
that transports heat from equatorial regions
towards the Arctic circle. Warm surface water
coming up from the tropics gives off heat
as it moves north until eventually, it cools
so much in northern waters that it sinks and
circulates back to the south. There it warms
again, rises and heads back north. The constant
sinking in the north and rising in the south
drives the conveyor. Global warming weakens
the circulation because increased meltwater
from Greenland and the Arctic icesheets along
with greater river run-off from Russia pour
into the northern Atlantic and make it less
saline which in turn makes it harder for the
cooler water to sink, in effect slowing down
the engine that drives the current....
1 December 2004. NASA
SATELLITES WITNESSED EL NIÑO CREEP
IN FROM THE INDIAN OCEAN. NASA
Earth Observatory News. El Niño has
fascinated people for centuries, and continues
to interest people around the world, because
it changes global weather patterns....Just
in time for this Christmas, an index created
to see the development of El Niño events
received the approval of the scientific community.
Scott Curtis, a NASA-funded scientist from
East Carolina University in Greenville, N.C.
and colleagues, created an index using satellite
data of rain and winds in the eastern Indian
Ocean that accurately predicted the arrival
of the 2002-2003 El Niño. ... Curtis
... and Robert Adler, George Huffman and Guojun
Gu, all of NASA's Goddard Space Flight Center,
Greenbelt, Md. used NASA's Tropical Rainfall
Measuring Mission (TRMM) and QuikScat satellite
data ranging from November 2001 to March 2002.
...The researchers developed the El Niño
Onset Index (EOI) using the rainfall data
alone. "Because the rainfall data has
been a consistent indicator of an on-coming
El Niño, as compared to the wind data,
only the rainfall data was used to construct
8 November 2004. NASA
RELEASE: 04-369. TRMM Satellite Proves El
Niño Holds the Reins on Global Rains. NASA
scientists recently found the El Niño
Southern Oscillation (ENSO) is the main driver
of the change in rain patterns all around
the world. The NASA and Japan Aerospace Exploration
Agency (JAXA) Tropical Rainfall Measuring
Mission (TRMM) satellite has enabled scientists
to look around the globe and determine where
the year-to-year changes in rainfall are greatest.
By studying the rain patterns in these areas
over the past 50 years, with rain gauge data
prior to 1998, they established the main component
of this change in global rainfall is directly
correlated with the El Niño Southern
Oscillation. The study appeared in a recent
issue of the Journal of Geophysical Research-Atmospheres.
15 April 2004. NASA RELEASE: 04-130. SATELLITES
RECORD WEAKENING NORTH ATLANTIC CURRENT. A
North Atlantic Ocean circulation system weakened
considerably in the late 1990s, compared to
the 1970s and 1980s, according to a NASA study.
Sirpa Hakkinen, lead author and researcher
at NASA's Goddard Space Flight Center, Greenbelt,
Md. and co-author Peter Rhines, an oceanographer
at the University of Washington, Seattle,
believe slowing of this ocean current is an
indication of dramatic changes in the North
Atlantic Ocean climate. The study's results
about the system that moves water in a counterclockwise
pattern from Ireland to Labrador were published
on the Internet by the journal Science on
the Science Express Web site at: http://www.sciencexpress.org.
The current, known as the sub polar gyre,
has weakened in the past in connection with
certain phases of a large-scale atmospheric
pressure system known as the North Atlantic
8 March 2004. From science@NASA -- A
Chilling Possibility. By
disturbing a massive ocean current, melting
Arctic sea ice might trigger colder weather
in Europe and North America.
5 January 2004. NASA RELEASE: 04-007. EL
NINO-RELATED FIRES INCREASE GREENHOUSE GAS
changes in concentration of carbon dioxide
and methane, two important greenhouse gases
in the atmosphere, can be linked to fire activity
associated with the El Nino-La Nina cycle,
according to a study conducted by a team of
NASA scientists and other researchers....
Scientists today are trying to understand
the relationship between the carbon cycle
and the climate system. The carbon cycle is
the movement of carbon, in its many forms,
among the biosphere, atmosphere, oceans and
the geosphere. The cycling of carbon affects
the amount of carbon-based greenhouse gases
in the atmosphere and thus the Earth's climate.
This study shows carbon loss in the biosphere
over the next several centuries may be sensitive
to the intensity and variability of El Nino-induced
September 2003. El
Nino damage in California. NASA's
Earth Observatory. In anticipation of the
1997-98 El Niño, the U.S. Federal Emergency
Management Agency spent approximately $165
million to prepare for storms and heavy rain
in California. Local governments distributed
sandbags to residents for flood protection,
established volunteer programs to remove debris
from storm drains, monitored high flood risk
areas, and provided special training to damage-control
teams. All of this preparation was possible
because the 1997-98 El Niño had been
forecast six months in advance.
14 March 2003. A
Quirky El Niño. (science@NASA) The
2002-03 El Niño has resisted stereotypes
with its unpredictable behavior. ...Sometimes
Earth scientist Bill Patzert wishes he had
a degree in psychology. It might help him
understand El Niño. "Every El
Niño has a personality all its own,
and the latest one has been very quirky," says
Patzert, who works at NASA's Jet Propulsion
Laboratory. "Here in southern California
we expect El Niño to bring heavy rains.
But the weather this winter has had a split-personality,
alternating between warm and dry months to
very cold and wet months."
August 2002. SATELLITES
REVEAL A MYSTERY OF LARGE CHANGE IN EARTH'S
GRAVITY FIELD -- Satellite
data since 1998 indicates the bulge in the
Earth's gravity field at the equator is growing,
and scientists think that the ocean may hold
the answer to the mystery of how the changes
in the trend of Earth's gravity are occurring.
Goddard Space Flight Center RELEASE: 02-147
April 2001. NASA
DEMONSTRATES HOW EARTH'S GLOBAL HEAT ENGINE
DRIVES PLANT GROWTH. Scientists
at NASA GSFC have assembled the first long-term
global data set that demonstrates the connection
between changing patterns of sea surface temperature
and patterns of plant growth across the Earth's
March 2001. AFTER
THREE STRIKES, IS LA NINA OUT? Last
Autumn scientists thought La Nina had faded,
but recent NASA satellite images revealed
La Nina-like conditions lurking in the Pacific
for the third year in a row. Will they linger
a fourth? Some climate models predict La Nina
will vanish in 2001 and that a weak El Nino
could take its place. A shift from La Nina
to El Nino conditions would likely trigger
more rainfall in California where swelling
rivers will increase the output of hydroelectric
dams, providing the state with some much needed
electricity. La Nina-like conditions that
have persisted in the Pacific Ocean for three
years might finally subside this Fall. The
change could pave the way for a weak El Nino
-- and a surge of hydroelectricity for power-starved
January 2001. RAINFALL
CHANGE MAY GIVE EARLIER SIGNAL OF EL NINO. A
decrease in rainfall over the Indian Ocean
may give the world the earliest signal that
a strong El Nino is about to start. US
Global Change Research Program (USGCRP)
August 1999. El
Niño. NASA Earth Science Enterprise
Series, Fact Sheet: NF-211 [97KB PDF] El
Niño effects are not limited to the
disturbed areas off of Peru and Ecuador. They
can be transmitted great distances. In many
parts of the world, the disruption of normal
climate can have tragic and/or profound economic
June 1999. La
Niña. NASA Earth Science Enterprise
Series, Fact Sheet: FS-1998-08-017-GSFC [250KB
PDF] The coupled
atmosphere-ocean phenomenon known as El Niño
is frequently followed by a period of normal
conditions in the equatorial Pacific Ocean.
Sometimes, but not always, El Niño
conditions give way to the other extreme of
the El Niño-Southern Oscillation (ENSO)
cycle. This cold counterpart to El Niño
is known as La Niña, Spanish for "the
February 1998. Using
Satellites to Track Rift Valley Fever [200KB
PDF NASA Lithograph] Rift Valley Fever (RVF),
at least in the African country of Kenya,
has been well known for over 60 years. As
early as 1913, a disease fitting the description
of RVF was blamed for the loss of sheep in
the Rift Valley in kenya. However, it was
not until scientists studied an outbreak of
the disease in 1931 that a virus was isolated
and shown to cause the disease. By using satellites
to closely monitor the vegetation in the region
affected by increased rainfall, scientists
can identify likely habitats for the mosquitoes
that carry the RVF virus, and provide advance
warning of large-scale outbreaks of the disease.
Niño [405KB PDF NASA Lithograph] This
image shows the progression of the 1997-98
El Niño as derived from the TOPEX/Poseidon
Articles from 1998–present
NOAA's El Niño & La Niña web page - https://www.climate.gov/enso
Air-Sea Interactions - 15 multimedia resources from Teachers' Domain Earth and Space Science multimedia resources (movies and interactives).
El Niño/Southern Oscillation (ENSO) Diagnostic Discussion issued by Climate Prediction Center/NCEP
Reverberations of the Pacific Warm Pool - El Niño-like climate anomalies. E.g. the Indo-Pacific warm pool spanning western waters of the equatorial Pacific to the eastern Indian Ocean, holding the warmest seawaters in the world. Over decades, average annual temperatures increase and then decrease like a beacon, may affect climate in regions as far away as southern United States, and may be powerful enough to broaden the extent of El Niño.
Sea Level Viewer interactive tool at NASA's "Ocean Surface Topography from Space" Web site.
OceanWorld - An ocean-science web site by Texas A&M Universitywith info about ocean processes, links to teaching material and sources of real-time data. Also complete college-level and graduate courses in oceanography and physical oceanography.
NASA's Aqua Mission Aqua focuses on the multi-disciplinary study of Earth's interrelated processes (atmosphere, oceans, and land surface) and their relationship to changes in the Earth system. Data sets include atmospheric temperature and humidity profiles, clouds, precipitation and radiative balance; terrestrial snow and sea ice; sea surface temperature and ocean productivity; soil moisture.
NASA Ocean Currents animation.
USGS site (http://ga.water.usgs.gov/edu/) -- Earth water chart
ForgeFX Interactive 3D simulation by Prentice Hall - OCEAN WAVES - demonstrates the connection between wind speed and ocean particle motion depth.
Weather Topics -- From USA Today: climate change, El Niño/La Niña, ocean weather, hurricanes, snow & ice, weather satellites, and global weather patterns. Email weather-related questions to USA Today's weather page editor, Jack Williams.