Weather Forecast & Current Climate Conditions

The Technology & Economic Forum is a venue to discuss issues pertaining to Technological and Economic developments in India. We request members to kindly stay within the mandate of this forum and keep their exchanges of views, on a civilised level, however vehemently any disagreement may be felt. All feedback regarding forum usage may be sent to the moderators using the Feedback Form or by clicking the Report Post Icon in any objectionable post for proper action. Please note that the views expressed by the Members and Moderators on these discussion boards are that of the individuals only and do not reflect the official policy or view of the Bharat-Rakshak.com Website. Copyright Violation is strictly prohibited and may result in revocation of your posting rights - please read the FAQ for full details. Users must also abide by the Forum Guidelines at all times.
suryag
Forum Moderator
Posts: 3572
Joined: 11 Jan 2009 00:14

Re: Weather Forecast & Current Climate Conditions

Postby suryag » 14 Jul 2009 01:22

todays satellite picture

Why doesnt all that white thing on the pic translate to rain ?

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 14 Jul 2009 01:51

A simple wild guess answer based on school physics would be that the falling droplets are getting evaporated faster than the time they can take to travel all the way down to the ground as rain, ie the vertical temperature profile below those clouds are such as to prevent rain (condensed water vapor) to make it all the way to the ground before evaporation.

How do clouds and rain form?


Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 22 Jul 2009 20:40

NOAA Scientists Find Tsunami “Shadow” Visible from Space
The new research challenges the traditional belief that tsunamis are too subtle in the open ocean to be seen at the surface. The findings confirm a theory, developed by Godin and published in 2002-05, that tsunamis in the deep ocean can be detected remotely through changes in surface roughness.

So some of the existing instruments can potentially do Tsunami monitoring and other deep ocean disturbances that carry ;-) to the surface.
The new study presents a third way to detect tsunamis — by changes in the texture of the surface water across a wide span of the open ocean.

Godin’s research confirmed his theory that a tsunami wave roughens the surface water through air-sea interaction. First the leading edge of the tsunami wave stirs up the surface winds. Those same winds, which become more chaotic than the wave itself, then churn the surface waters along the slope of the wave.

Because rough water is darker than smooth water, a contrast forms between the dark, rough water of the wave and the bright, smooth water on either side of it. Common scientific instruments, called microwave radars and radiometers, are able to detect this contrast, known as a tsunami shadow.

merlin
BRF Oldie
Posts: 2153
Joined: 01 Jan 1970 05:30
Location: NullPointerException

Re: Weather Forecast & Current Climate Conditions

Postby merlin » 23 Jul 2009 09:58

Bade wrote:NOAA Scientists Find Tsunami “Shadow” Visible from Space
The new research challenges the traditional belief that tsunamis are too subtle in the open ocean to be seen at the surface. The findings confirm a theory, developed by Godin and published in 2002-05, that tsunamis in the deep ocean can be detected remotely through changes in surface roughness.

So some of the existing instruments can potentially do Tsunami monitoring and other deep ocean disturbances that carry ;-) to the surface.
The new study presents a third way to detect tsunamis — by changes in the texture of the surface water across a wide span of the open ocean.

Godin’s research confirmed his theory that a tsunami wave roughens the surface water through air-sea interaction. First the leading edge of the tsunami wave stirs up the surface winds. Those same winds, which become more chaotic than the wave itself, then churn the surface waters along the slope of the wave.

Because rough water is darker than smooth water, a contrast forms between the dark, rough water of the wave and the bright, smooth water on either side of it. Common scientific instruments, called microwave radars and radiometers, are able to detect this contrast, known as a tsunami shadow.


Would even 18k tons (probable max tonnage) cause enough disturbance to be noticed? Tracking is another matter entirely.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 23 Jul 2009 22:57

merlin wrote:Would even 18k tons (probable max tonnage) cause enough disturbance to be noticed? Tracking is another matter entirely.


I do not know the answer, if you mean an underwater staged event. How much below surface can one go with a device to rig a test to conceal its signature entirely. Keep in mind the resolution of geostationary payloads are poorer of ~ a few km. So, the event has to create fronts much much larger than this scale. Open question and classified, but not unexplored among the hyperactive species on earth is my guess.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 24 Jul 2009 01:11

Falling rain drops video

Why Raindrops Fall in Different Sizes
Instead, by analyzing high-speed movies of falling water droplets, Villermaux and Bossa found that the drops go through a series of shape-shifting moves and finally burst apart into a spray of multi-sized drops.

First, the falling spherical drop gradually flattens out into a pancake shape. As it gets wider and thinner, it eventually captures the air ahead of it and deforms into a shape something like an upturned plastic grocery bag, the study shows.

Mort Walker
BRF Oldie
Posts: 8342
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

Re: Weather Forecast & Current Climate Conditions

Postby Mort Walker » 09 May 2010 01:13

This is really sad:
Severe storm kills 54 in India

A sensor network and cheap weather radar, like US local TV stations have, would prevent these sort things happening and it would pay for itself back for crop planting/harvesting. Maybe this is something the Ministry of Agriculture should take up instead of the Met dept?

merlin
BRF Oldie
Posts: 2153
Joined: 01 Jan 1970 05:30
Location: NullPointerException

Re: Weather Forecast & Current Climate Conditions

Postby merlin » 10 May 2010 16:27

Bade wrote:
merlin wrote:Would even 18k tons (probable max tonnage) cause enough disturbance to be noticed? Tracking is another matter entirely.


I do not know the answer, if you mean an underwater staged event. How much below surface can one go with a device to rig a test to conceal its signature entirely. Keep in mind the resolution of geostationary payloads are poorer of ~ a few km. So, the event has to create fronts much much larger than this scale. Open question and classified, but not unexplored among the hyperactive species on earth is my guess.


Actually I was referring to Ohio class max tonnage and its tracking via surface disturbances.

Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

Re: Weather Forecast & Current Climate Conditions

Postby Singha » 10 May 2010 18:05

there is said to be a *finally* a doppler radar network coming up to give the kind of cloud maps weather.com users take for granted.

few days back they showed Hong kong airport and mentioned doppler radar has some drawbacks in certain climatic conditions.
so they have installed a "lidar" (some kinda laser) than fires beams into the nearby clouds and fills in this gap.

Murugan
BRF Oldie
Posts: 4191
Joined: 03 Oct 2002 11:31
Location: Smoking Piskobidis

Re: Weather Forecast & Current Climate Conditions

Postby Murugan » 02 Jun 2010 15:44

Tropical Storm Phet is brewing in Arabian Sea.

Landfall on Kutch and adjoining sindh by 4th June

Phet

SSridhar
Forum Moderator
Posts: 23843
Joined: 05 May 2001 11:31
Location: Chennai

Re: Weather Forecast & Current Climate Conditions

Postby SSridhar » 24 Oct 2010 12:06

Nowcast facilities in metros soon
Nowcast to predict the weather a few hours ahead in specific localities will be introduced in all metros, said Ajit Tyagi, Director-General of Meteorology, IMD, here on Saturday.

Inaugurating a satellite facility at the aerodrome meteorological office, he said the nowcast model was used successfully in the recently concluded Commonwealth Games to predict weather over each stadium.

Nowcast was used on a limited scale in New Delhi and would soon be extended to Mumbai, Chennai and Kolkata. This site-specific facility could predict rain in locations such as Nungambakkam, Meenambakkam and Adyar. The new facility, a direct readout ground station for receiving and processing data from polar orbiting satellites, would obtain high resolution images from these satellites in 1000 m, 500 m and 250 m spectral band resolutions. With the new facility, data on vertical profile of atmospheric temperature/humidity, sea surface temperature, stability of the atmosphere, its turbidity, optical depth of cloud and aerosol could be obtained.

As on date, the Chennai facility was receiving data from NOAA 18, NOAA 19, Modis Terra, Modis Aqua satellites launched by the National Oceanic and Atmospheric Administration (NOAA), Washington; and Fengyun 1D satellite from China. Once the European Space Agency's MetOp satellites begin transmission over the Indian region, the Chennai facility had the provision to receive the data, he said. A similar facility was installed in New Delhi in September. One such facility was being installed in Guwahati. Y.E.A. Raj, Deputy Director-General of meteorology, Regional Meteorological Centre, Chennai, said, “With nowcast, people organising functions such as marriages will be able to find out if it will rain in the locality.”

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 04 Nov 2010 20:40

Super cyclone threat looms over Diwali
Christened 'Jal,' the centre of pressure of the cyclone had reached 992 hpa (hecta pascals) on Wednesday afternoon as per the numerical models worked out by the experts. "Once the pressure lessens, the intensity of the cyclone increases. With higher wind speed, the cyclonic storm gathers momentum," said V S N Murthy, senior scientist at the National Institute of Oceanography (NIO). As the upper air cyclonic circulation is very intense, the chances of formation of a super cyclone are high, he said.

Once a severe cyclonic storm turns into a super cyclone, it would result in very heavy rains, accompanied by gusty winds of 210-260 km speed. "It can destroy pucca houses, uproot big trees and disrupt the entire communication network. It could also cause immense damage to ports and flatten coastal villages as tidal waves could rise up to a height of 14 metres," an expert said.

O Bhanukumar, senior professor in Andhra University, said the cyclone threat is plausible as the low pressure radius is spread across 500 km in the sea. "While it weakened after it hit the land at the Gulf of Thailand, it has intensified again thanks to high sea surface temperature. During Oct-Nov, the AP coast is most vulnerable to cyclonic storms and they last for 5-6 days," he reasoned.

A Jayaraman, director, National Atmospheric Research Laboratory, said once the wind speed crosses 60 km it could turn into a deep depression. "The sea gets very rough with gales of 120-150 km speed once it becomes a cyclone," he said. Corroborating this, J V M Naidu of Cyclone Warning Centre, Visakhapatnam, said November has always been a month of cyclones in the state. "The vigorous north-east monsoon and depression are a deadly combination. With the north-south winds active, the likelihood of a cyclone hitting the coast cannot be ruled out," he said. In the last one decade alone, the state has experienced 54 cyclones.

Read more: Super cyclone threat looms over Diwali - The Times of India http://timesofindia.indiatimes.com/city ... z14KQEvu6A

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 04 Nov 2010 20:45


Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 23 Jul 2012 21:28

http://news.yahoo.com/indian-scientists-try-crack-monsoon-source-code-110610453--business.html
NEW DELHI/BHUBANESHWAR (Reuters) - Scientists aided by supercomputers are trying to unravel one of Mother Nature's biggest mysteries -- the vagaries of the summer monsoon rains that bring life, and sometimes death, to India every year.

In a first-of-its-kind project, Indian scientists aim to build computer models that would allow them to make a quantum leap in predicting the erratic movements of the monsoon.

If successful, the impact would be life-changing in a country where 600 million people depend on farming for their livelihoods and where agriculture contributes 15 percent to the economy. The monsoon has been dubbed by some as India's "real finance minister".

"Ultimately it's all about water. Everybody needs water and whatever amount of water you get here is mainly through rainfall," said Shailesh Nayak, secretary of the Earth Sciences Ministry.
.......

Working with counterparts in the United States and Britain, Indian scientists are trying to crack the monsoon's "source code" using super-fast computers to build the world's first short-range and long-range computer models that can give much more granular information about the monsoon's movements.

......

There is a lot the IMD struggles to predict -- when the rains will arrive throughout the country, where exactly they will fall, which parts will receive the most and how long they will last. Short-range forecasts give more precision but offer only a five- to seven-day window into the future, which farmers say is too short.

The monsoon mission aims to extend those short-term forecasts to at least 15 days and enable the weather office to give much more detailed seasonal projections.

The best predictions are for up to 384 hrs into the future of model runs, used also by weather service in massa at a granularity of ~ 100km.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 09 Aug 2012 00:06

http://www.agu.org/journals/eo/v093/i03 ... abloid.pdf
Eos: The concept of abrupt climate change did not really exist prior to the early 1990s. What
was the dominant view before this time, and what made researchers change their minds?
Rashid: The defining moment for abrupt climate change research came in 1993 when
Willi Dansgaard and his colleagues published oxygen isotope records for Greenland
ice core samples that showed the air temperature swinging back and forth, meaning
warming and cooling, over periods as short as a thousand years. Those temperature
swings are now famously known as Dansgaard-Oeschger (D-O) oscillations, and
though they were first discovered in Greenland ice cores, they were later observed in
North Atlantic marine sediment samples. In subsequent studies, these abrupt climate
events were found any place on Earth that was studied sufficiently, including Antarctica,
the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and even on land if you
look at the climate record as captured in cave mineral deposits.
Prior to this, the main argument in paleoclimate or paleoceanographic research was
that the climate is governed by Milankovitch forcings—cycles related to the position
and angular orientations of the Sun and the Earth—that cause the climate to change in
100,000-year, 41,000-year, and 21,000-year cycles. These cycles are driven by the eccentricity
or procession of Earth’s orbit, and the planet’s obliquity, or axial tilt. At that
time, these were considered abrupt climate change, but we now know that is not accurate.
Before the advent of the Greenland ice core isotope record the idea of abrupt climate
change, meaning a shift from warm to cold in a couple of decades, did not exist. Even
though some modelers may have thought so, there was no data documenting it.
Eos: What is the primary mechanism of abrupt climate change?
Rashid: If you polled climatologists, probably 99% of them would agree that the interaction
between freshwater in the North Atlantic and the Atlantic Meridional Overturning Circulation
(AMOC) is the biggest driver of abrupt climate change. So the idea is that, in the
past, there was a big ice sheet sitting on North America that would shed icebergs. These icebergs
would float along the surface of the North Atlantic where they would eventually
melt, forming a freshwater cap on the ocean’s surface. As a result, the formation of North
Atlantic deep water would slow down, and the AMOC would weaken. This weakening
reduces the amount of heat and moisture exchange into the atmosphere, and as a result,
the entire North Atlantic would start to cool. That cooling at first propagated to northwestern
Europe, then all the way to Eurasia, and would be associated with an increase in sea
ice. In the Southern Hemisphere, however, there would be a reverse effect. Because the
AMOC is no longer transporting as much heat into the Northern Hemisphere, it would accumulate
in the south. The temperature would go up, and the extent of sea ice around Antarctica
would decrease. Alongside these thermal changes, there would be an effect on the
hydrological cycle in the tropics. From paleogeochemical proxies, we can prove that the
AMOC was significantly weakened during Heinrich Event 1—a period of sudden global
climate change that persisted for less than 1000 years—but this is something we cannot
clearly demonstrate for D-O events.
Eos: If the Atlantic Meridional Overturning Circulation were to weaken or collapse because
of modern climate change, as some scientists have predicted, what would be the result?
Rashid: I think it is important to keep in mind that the geographic configuration was
very different during the immediate past glacial-interglacial cycle than it is now. If we think about the Younger Dryas or Heinrich events, the amount of freshwater available
to perturb the AMOC was much larger than it is now. However, we still have a huge
ice sheet on Greenland. And, if we continue to increase the atmospheric carbon dioxide
concentration, then more Arctic sea ice will melt. Add to this the freshwater runoff from
the repeatedly freezing and thawing northern continents, such as Siberia or northern
Canada, and there will be the potential to add enough freshwater to the North Atlantic
to perturb the AMOC. So, the question is, how different will the AMOC weakening be
for the future climate as compared to past climates? Based on modeling work we do anticipate
that if we add freshwater to the North Atlantic there will be cooling in the Northern
Hemisphere. If the AMOC somehow weakens, even by as little as 20% or 30%, there will be
a significant amount of cooling downwind, meaning England, Iceland, Norway, and the
rest of western Europe. But the impact is not going to be restricted to these places. It will also affect the large populations in China and India, by reducing or modifying the monsoon, and it will also affect the United States’ eastern seaboard.
Eos: What is your area of research? How do you go about piecing together a coherent picture of an ancient climate?
Rashid: My expertise is in paleoceanography, and in my research I use isotope geochemistry and interpret the concentrations of minor and trace elements. At present, most of my work is in biogenic carbonates, studying the chemistry of organisms that lived at the surface or grew at the bottom of the ocean.

By measuring isotope ratios and the concentrations of minor and trace elements trapped in the calcite shells of ancient single-celled organisms, I can reconstruct past temperatures, past ocean circulations,
and past hydrological cycles. As an example, in the book I have a chapter related to the Younger Dryas, a period of sudden cooling that started roughly 12,900 years ago and interrupted the gradual warming
of deglaciation. During this time there was freshwater sitting on North America in two proglacial lakes: Lake Agassiz and Lake Ojibway. This freshwater somehow got into the North Atlantic, leading to a 1200-yearlong or 1300-year-long cooling period in the Northern Hemisphere. The Younger Dryas,
however, is a “Big Foot” story. Big Foot, the quintessential American fairy tale, is blurry. That’s the problem. The Younger Dryas is one of the most highly contested issues in the past 50 years of climate change research. There are people who have made their reputations working on the Younger Dryas. Yet,
no one has been able to find the signature of this freshwater flux in the North Atlantic. No one. If you look at the Greenland ice core record, or the Asian monsoon record, or the cave deposit record, you can clearly see the Younger Dryas. But in the North Atlantic, where everyone says that meltwater came
and weakened the AMOC, no one has been able to find any sign of that freshwater. So, in the book, I took a stab at this issue; I provided an alternative explanation as to why you should not be expecting a meltwater or freshwater signature in the North Atlantic. Briefly, my idea is that during the Younger Dryas, freshwater admixed with fine-grained sediments were discharged underneath the Laurentide ice sheet through the Hudson Strait ice stream, like a river with fine-grained sediments. Since this freshwater runoff could not float freely on the top of the ocean due to its higher density, these waters would sink
close to the bottom of the ocean. Over time, the suspended sediment would slowly rain down, and the meltwater would rise back toward the surface. But, by the time this meltwater made its way back up to the surface it would have lost its original isotopic signature. This is why you do not see, and should
not expect to see, a meltwater signature associated with the Younger Dryas in the North Atlantic. This is what we documented in our sediment cores from in and around the Hudson Strait region, a 1-meter thick Younger Dryas sediment unit with a negligible freshwater isotopic signature.
Eos: The book discusses in some detail the effects of abrupt climate change on long gone civilizations. How do some scientists think an early society living along the tributaries of the Indus River in India met its end?
Rashid: In the monograph, B. S. Paliwal discussed the fate of the Vedic civilizations that flourished along the banks of the Sarasvati and Drishadvati rivers more than 12,800 years ago. He discussed how tectonic activity at the time could have negatively affected the strength of the rivers, which led to the
formation of saline lakes. As a result, this disorganized drainage system ushered in the appearance of lakes, reversed the rivers’ courses, and blocked water flow. It is now accepted that the Indian summer monsoon, commonly known as the southwest monsoon, was strong and wet during the early Holocene (11,000–6000 years ago) and that may have resulted in frequent flooding. As Paliwal suggests, this flooding might have caused the end of the Vedic civilization, though we have very little evidence to verify
or confirm this hypothesis at present
.
the understanding of abrupt climate change
affected scientists’ perceptions of the risks
and consequences of modern anthropogenic
climate change?
Rashid: I think it has significantly
changed the way that a majority of climate
scientists think. If you look at my mentors,
who are in their 60s or 70s, and you look at
the papers they have written in their early
years, they tend to focus on solar insolation,
astronomical theory, and Milankovich
cycles. So, compared to them, we are basically
a completely different crop of scientists;
my professors were worried about centuries,
we are worried about decades. The
understanding of the potential for abrupt climate
change has led to two different urgencies
and two different sets of worries, which
I think comes across in the book. Unfortunately,
some of these adverse changes might
be seen in our lifetimes. That is probably
one of the things that really got us up on our
feet and working as feverishly as possible to
convince the wider society about the importance
of climate change.
Eos: What is the future of abrupt climate
change research?
Rashid: At present, we are really only able
to prove that the AMOC weakened or slowed
down for two events: the Younger Dryas and
Heinrich Event 1, which took place from 11,700
to 12,900 and 15,000 to 16,400 years ago, respectively.
But there are other climate transitions for
which we need a better understanding, such as
Glacial Termination II, which took place 141,000
years ago. In other cases, such as 60,000 or
125,000 years ago, we have no clue what the climate
looked like during those times. So, we’ve
just scratched the surface.
This really is the cutting-edge research in climate
science. Abrupt climate change research
is the brand new science in the Earth sciences,
and I see the field getting stronger and attracting
many bright students. I think the field will
be going strong for at least the next 20 years.


Too much indented ones need editing. Sorry can't do it all. But the material is worth reading and captures the overall picture on abrupt climate change.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 20 Jun 2013 02:16

Another IMD report post-facto on the Leh event from Aug 2010.

http://www.imd.gov.in/doc/cloud-burst-over-leh.pdf

Simulation of Himalayan Cloudburst event from July 2003.
http://www.ias.ac.in/jessci/jun2006/0501.pdf

http://www.currentscience.ac.in/Volumes/102/02/0327.pdf
Catastrophic hydrological event of 18 and 19 September 2010 in Uttarakhand, Indian Central Himalaya – an analysis of rainfall and slope failure

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 26 Nov 2013 00:19

http://press.web.cern.ch/press-releases ... ate-change

This is going to be something to keep watch on as it relates to climate and impact of cloud formation.

Amines are atmospheric vapours closely related to ammonia, and are emitted both from human activities such as animal husbandry, and from natural sources. Amines are responsible for odours emanating from the decomposition of organic matter that contains proteins. For example, the smell of rotten fish is due to trimethylamine. The CLOUD experiment’s unique ultra-clean chamber allowed the collaboration to demonstrate that the extremely low concentrations of amines typically found in the atmosphere - a few parts per trillion by volume - are sufficient to combine with sulphuric acid to form highly stable aerosol particles at high rates.

The measured sensitivity of aerosol formation to amines came as a surprise, and points to a potentially significant climate cooling mechanism. Moreover, since amine scrubbing is likely to become an important technology for capturing carbon dioxide emissions from fossil-fuelled power plants, this effect is likely to rise in future.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 27 Nov 2013 02:05

Another dangerous looking cyclone 'Lehar' is heading for the East coast. Folks should take shelter and keep an eye on it.

http://www.thehindubusinessline.com/ind ... 394364.ece

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 27 Nov 2013 23:14

Lehar has weakened and is now estimated to have winds of 160 kmph. Still keep an eye out.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 17 Dec 2013 08:20

News Picks : Global warming is causing North Pole to change direction
New Scientist: The melting of Earth’s glaciers and ice sheets is affecting the movement of the North Pole. Since 1899, when observations began, the pole’s position had been drifting southward about 10 cm per year due to changes in the distribution of Earth's mass. But in 2005 it changed direction and started moving eastward. To find out why, Jianli Chen of the University of Texas at Austin and his colleagues used data from NASA’s GRACE (Gravity Recovery and Climate Experiment) satellites. They found that the melting of the Greenland and Antarctic ice sheets and mountain glaciers, and the resulting change in sea level, account for 90% of the eastward shift. "The driving force for the sudden change is climate change,” says Chen, who presented the group’s findings at the annual fall meeting of the American Geophysical Union in San Francisco.
:eek:

Vayutuvan
BRF Oldie
Posts: 10442
Joined: 20 Jun 2011 04:36

Re: Weather Forecast & Current Climate Conditions

Postby Vayutuvan » 24 Feb 2014 02:09

Bade and others trained/interested in climate and weather modeling -

How Well Do Our Climate Models Match Our Observations?
"According to recent articles by Roy Spencer and John Christy, our climate models have done a poor job of predicting warming due to humans burning fossil fuels. They claim that we've observed only a fraction of the warming they predict. But when I look at the source they claim to use, the State of the Climate in 2012, I see that it shows a warming of 0.7 degrees Celsius worldwide since 1980, close to the 0.8 degrees Celsius warming predicted by the climate models. Take a look at the data for yourself. How well do our predictions match our observations?"


If possible go through some of the comments by Geoffrey Landis.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 24 Feb 2014 03:11

Christy has been a known nay-sayer for a long time now. He puts a lot of emphasis on Atmospheric data to draw his conclusions. There is the 800 lb gorilla the ocean which is also warming and which has huge effect in regulating weather and climate, think specific heat of water vs air. Then there are the uncertainties in model building to understand anthropogenic contributions to this mix. So that is the easiest beating boy if you want to pull down the predictions.

The only reason for "consensus science" in climate studies is that if things are warming or changing for worse, humans would like to reverse it if possible. It is an human engineering issue not a science issue really hence consensus is required for implementation. The changes recommended affect the way we live on earth and the recommendations are not disastrous to our existence. So all this is a political policy issue, which uses science results with all the uncertainties everyone understands, even the ones who recommend it.

At least that is the way I have understood the whole thing.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 24 Feb 2014 03:21

New Indian Institute of Tropical Meteorology climate model to increase forecast accuracy
PUNE: The Indian Institute of Tropical Meteorology (IITM), one of the premier research institutes under the ministry of earth sciences (MoES), has developed a new climate model of its own, which aims at providing a fair assessment of the impact of climate change over a period of 100 years on the behaviour of monsoon.

"We have successfully coupled the atmospheric model with a new oceanic model to develop a climate model of our own. The next phase involves addition of aerosols and biogeochemistry elements for forecasting purpose in future," IITM director B N Goswami told reporters on Tuesday. "The project forms a part of the Mission Monsoon goal and will lead to a more accurate long-range forecasting system," he added.

According to MoES secretary Shailesh Nayak, the dynamical coupled model has proved more accurate as compared to the traditional statistical model of seasonal forecast. "Our coupled model forecast of monsoon this year was right on the dot. We had forecast the long-period average rainfall for the season to be between 104% and 108% and the actual rainfall realised was 106%. As against this, the forecast of 98% rainfall using the statistical model was off the mark," he said.

Nayak added that the ministry plans to replace the statistical weather forecasting model with the dynamical coupled model by 2017. "All efforts are on in this direction. The capacity building and investments made in the recent years are showing results, especially when it comes to short-range forecast, ie, forecast for five days. We have been able to successfully forecast severe cyclones like 'Phailin', 'Helen' and 'Lehar' and even earlier, cyclones like 'Thane' and 'Neelam'," he said.

Nayak attributed the enhanced short-range forecasting capabilities to a combination of measures, such as improved ocean and atmospheric observation infrastructure and network, installation of high computing systems that have allowed the forecasting agencies to run and experiment with different models, induction of 200 expert meteorological scientists, strengthening of training schools for scientists, and collective work by various institutions under the MoES."

Nayak added that the kind of accuracy currently achieved in short-range forecast did not exist before 2009
. "Our focus now is on improving the long-range forecasting, with the IITM having already started issuing forecast for three-week periods during this monsoon and other institutes working on an extended forecast."

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 24 Feb 2014 03:37

Bade wrote:It is an human engineering issue not a science issue really hence consensus is required for implementation.


This is absolutely correct. The question is merely one of where the money gets spent.

For instance ~ $30 billion has been spend 'armoring' New Orleans from another Katrina. But is if the Oceans rise 2 feet, all this engineering will be wasted. The East coast is slowly getting ready for the massive spending need to protect cities after Sandy. The question is do we spend to slow climate change or spend to deal with the consequences. for India, with its fickle monsoon and long densely populated coast, the choices are all bad ones.

Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 24 Feb 2014 03:47

Unfortunately, all mitigation efforts will not keep everyone happy, and often times the choices are not crystal clear which leads to bitter fights and accusations even within the science community as some scientists have taken open positions regarding policy issues.

I happened to listen to a talk of someone high up in the ministry of earth sciences in India recently on climate change, and they are already drawing their own conclusions on intensification of cyclones there due to long term ocean warming. At least within government circles there is a consensus across the board. Policy implementation which affects commerce, there could be differences and negotiations.

Neshant
BRF Oldie
Posts: 4850
Joined: 01 Jan 1970 05:30

Re: Weather Forecast & Current Climate Conditions

Postby Neshant » 02 Apr 2014 11:02

John Casey - COLD SUN -


Bade
BRF Oldie
Posts: 7212
Joined: 23 May 2002 11:31
Location: badenberg in US administered part of America

Re: Weather Forecast & Current Climate Conditions

Postby Bade » 06 May 2014 19:28

You all are going to get flooded out in the coasts...move inland slowly.

East Antarctica melt could cause a global coastal destruction
Parts of the vast ice sheet of East Antarctica - which collectively holds enough water to raise global sea levels by 53 metres - could begin an irreversible slide into the sea this century, causing an unstoppable process of global coastal destruction, scientists have warned.

East Antarctica is widely considered to be more stable than the West Antarctic ice sheet but a study suggests that a large region of the eastern ice sheet is in danger of becoming irreversibly unstable once a relatively thin section of retaining ice on its coast is lost, the researchers said.

A slab of coastal ice is all that is stopping the giant Wilkes Basin ice sheet from slipping into the sea. Once this process begins it will relentlessly continue to pour vast amounts of water into the oceans for centuries to come, raising global sea levels by between three and four metres, they said.

"East Antarctica's Wilkes Basin is like a bottle on a slant and once uncorked it empties out," said Matthias Mengel of the Potsdam Institute for Climate Research in Germany, and lead author of the study published in the journal Nature Climate Change.





"The East Antarctic ice sheet has long been considered to be stable even under a warmer climate, in contrast to its West Antarctic counterpart. We have now shown that this may not be true," Mr Mengel said.

"This implies that the future sea-level contribution of the East Antarctic ice sheet may be significantly higher than previously estimated. This is important for the millions of people who live on the coasts. Every centimetre of sea level rise on top of what is already expected is going to be even more difficult to adapt to," he said.

"By emitting more and more greenhouse gases we might trigger responses now that we may not be able to stop in the future," he added.

East Antarctica holds about 10 times the volume of ice than is smaller West Antarctic cousin. Much of the ice in the east lies at high altitude and is kept well below freezing point, but a large proportion of it - enough to raise sea levels by 19 metres - lies on bedrock that is below sea level, such as the Wilkes Basin.

Scientists had considered even this low-lying part of the East Antarctic ice sheet - the so-called marine ice sheet - to be more stable and less likely of disintegrating in a warmer climate than the marine ice sheet of the West Antarctic.

However, the analysis the underlying bedrock on which the marine ice sheet of Wilkes Basin stands suggests this is not the case. The scientists found that the rock, which is below sea level and therefore more vulnerable to climate change, becomes a raised ridge at the coast which allows the ice to form a protective plug between the ocean and the ice sheet on the land behind it.

Computer modelling shows that if the local ocean temperatures around the East Antarctic rise as a result of global warming, the ice plug will continue to melt to a point where the "bottle" of ice held within the Wilkes Basin becomes "uncorked".

"Once started, it becomes unstoppable. At the moment it's still stable but if it melts then the ice plug alone will result in a global sea-level rise of between 5 and 8 centimetres, but the ice that it will release is going to cause 80 times that amount of sea-level rise," said Professor Anders Levermann of the Potsdam Institute.

"The bottle is so much bigger than the cork and these plugs of ice on the coast are so much smaller than the ice that they are keeping in place," Professor Levermann said.

The Intergovernmental Panel on Climate Change (IPCC) said that estimating future sea-level rise was one of the most difficult areas to predict, partly because of the unknown effects in the Antarctic. In its last report, published in March, the IPCC said that Antarctica's total sea level contribution would be up to 16cm this century, but if half of this ice loss occurred in the ice-cork region, the irreversible discharge of Wilkes Basin ice into the sea will begin, Professor Levermann said.

"Unfortunately we don't know whether we've initiated this process yet. It's fair to say that if we continue unmitigated climate change and global warming then we'll destabilise parts of Antarctica and trigger a discharge of ice that will not stop for centuries," he said.

"It may not be an imminent threat but it will change the planet and will have an impact on global culture because of the huge loss of the cultural heritage of the people living near the coasts," he added.

"We have probably overestimated the stability of East Antarctica so far....Until recently, only West Antarctica was considered unstable, but now we know that its ten-times-bigger counterpart in the East might also be at risk," professor Levermann said.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 16 May 2014 21:11

Monsoon might be delayed. Usually the winds have started by now and arrived in South Andamans. This year there is no sign of the atmosphere organizing itself.

Keep your fingers crossed folks.

http://www.business-standard.com/articl ... 147_1.html
“We are expecting a slight delay in the monsoon onset than the normal date of arrival,” Reuters quoted D S Pai of IMD as saying. The delay, even slightly, may not augur well since IMD expects the southwest rain to be slightly below normal. It had earlier forecast rain to be at 95 per cent of the Long-Period Average (LPA, an average of the past 50 years), which is 89 cm. Monsoon rainfall of 96-104 per cent of the LPA is considered normal.

IMD had also said there was a 60 per cent chance of the dreaded El Niño weather phenomenon, which causes low rain, to impact India's southwest monsoon. In the recent past. the years 2002, 2004 and 2009 were drought ones for this reason.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 19 May 2014 00:28

After a few days delay the monsoon has settled in over Andaman Sea. The mainland is not organizing itself yet so still a delayed monsoon.

http://www.thehindubusinessline.com/mar ... 022909.ece

merlin
BRF Oldie
Posts: 2153
Joined: 01 Jan 1970 05:30
Location: NullPointerException

Re: Weather Forecast & Current Climate Conditions

Postby merlin » 22 May 2014 15:51

BoB arm is active. Arabian Sea arm has not yet started to be active. Counter cyclonic air circulation over MP is the cause, until that dissipates, monsoon over Kerala will not start.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 03 Jun 2014 06:36

Monsoon is delayed. IMD hopes for a June 5th arrival in KL. Despite the absence of blocking circulations currents are very weak.

ramana
Forum Moderator
Posts: 54275
Joined: 01 Jan 1970 05:30

Re: Weather Forecast & Current Climate Conditions

Postby ramana » 14 Jun 2014 01:09

From Hindu on El Nino effect

Image

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 23 Jun 2014 13:10

I think we have to brace ourselves for a drought monsoon. The monsoon winds sweeping in are low in moisture and not sustaining heavy rainfall. Things will remain relatively dry for 2-3 more weeks. All one can do is pray for more moisture.

http://indiatoday.intoday.in/story/drou ... 68096.html

India is staring at the spectre of a possible drought as the progress of the monsoon has been abysmally slow, with authorities saying cumulative rainfall across the country has been 45 per cent below the average for this period. Reason: the El Nino effect is adversely affecting this year's monsoon, say weather experts.

The India Meteorological Department (IMD), in its latest report, has highlighted the weak and delayed onset of the monsoon. An analysis for the period from June 1-18 showed that rainfall has been deficient across the country.

The cumulative rainfall across the country has so far been 45 per cent below the Long Period Average (LPA) for 1951-2000. More worryingly, rainfall was 53 per cent below the average in northwest India.


Read more at: http://indiatoday.intoday.in/story/drou ... 68096.html

Image

Javee
BRF Oldie
Posts: 2377
Joined: 13 Jan 2003 12:31
Location: NJ

Re: Weather Forecast & Current Climate Conditions

Postby Javee » 23 Jun 2014 19:44

Central India river basins are predicted to be rainfall deficient this year. Godavari and Krishna may not flow well this time and I hope Telengana and AP can share the resources better unlike TN and KA. Marathwada will be hammered this year as well, there are already 400 odd suicides, looks like it is not going to end well for them.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 25 Jun 2014 20:38

This monsoon is terrifying me. There is no sign of revival. This month is flirting with the worst june rainfall ever recorded.

Theo_Fidel

Re: Weather Forecast & Current Climate Conditions

Postby Theo_Fidel » 27 Jun 2014 20:23

Today
Rain in Kerala : Nil
Rain in TN : Nil
Rain in Karnataka : 1 cm in Bijapur.

I have never seen anything like this. Zero rain in last week of june in KL. :eek:

http://www.imdchennai.gov.in/rdwr.htm
REGIONAL DAILY WEATHER REPORT FOR TAMIL NADU, PUDUCHERRY,

ANDHRA PRADESH, KARNATAKA, KERALA AND LAKSHADWEEP

FRIDAY 27TH JUNE 2014 / 06TH ASHADHA, 1936 (SAKA)


The chief amounts of rainfall recorded in centimetres are:

TAMIL NADU: Nil.

KERALA:Nil.

KARNATAKA: Basavakalyan (Bidar dt) and Zalki (Bijappur dt) 1 each.

Javee
BRF Oldie
Posts: 2377
Joined: 13 Jan 2003 12:31
Location: NJ

Re: Weather Forecast & Current Climate Conditions

Postby Javee » 27 Jun 2014 23:20

It is sweltering in Chennai, the sea-breeze typically sets in early evening, because of the prevailing dry heat on land, this is getting delayed. Chennai is racing towards record temperature that was set in 1948 (43.5 deg). We will also roast onlee :(

Javee
BRF Oldie
Posts: 2377
Joined: 13 Jan 2003 12:31
Location: NJ

Re: Weather Forecast & Current Climate Conditions

Postby Javee » 28 Jun 2014 16:43

Finally rain in Chennai, had a good pour for 30 mins.

merlin
BRF Oldie
Posts: 2153
Joined: 01 Jan 1970 05:30
Location: NullPointerException

Re: Weather Forecast & Current Climate Conditions

Postby merlin » 01 Jul 2014 12:41

Western arm of the monsoon (the Arabian sea one) is not showing any signs of revival. KA, KL, Goa and MH are going to be raped this year. At least it looks like that now. Unheard of rainfall deficiency in places like Mumbai.

Not just Krishna and Godavari, the Cauvery is also going to be badly affected by this. One of its major tributaries is the Kabini originating in Kerala and its not raining much in Wyanad as well.

Looks like El Nino is going to screw us this time and no IOD to offset it as well.


Return to “Technology & Economic Forum”

Who is online

Users browsing this forum: No registered users and 10 guests