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Stochastic and interruptible electricity sources

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by Kumar David

As the country moves towards increased generation from renewable sources the public will need to learn a little bit about some peculiar aspects of wind and solar power. I will call them the stochastic (S-word) and the interruptible (I-word) nature of both. They are related but for the engineer the implications are different. The S-word says the wind may blow like crazy all night but come morning it’s becalmed and may not pick up again till god knows when. (“The wind bloweth where it listeth, but thou canst not tell whence it cometh and whither it goeth”: John 3.8). More troublesome is the I-word, quick and intermittent fluctuations between furious force and stately calm. The chaps in the Control Room tear their hair out when a large quantum of wind power freaks out suddenly. Imagine if one Vitoria-equivalent of wind power splutters on and off like a car with a petrol block. I will explain how the control people deal with it.

Similar things happen with solar; it’s a beautiful sunny day but quickly darkens with rain. It’s clear morning but clouds drift across and cut the insolation on the panels. Oh hell!

Shall I compare thee to a summer’s day?

Thou art more lovely and more temperate:

Fresh winds do shake the darling buds of May,

And summer’s lease has all too short a date:

And often is his gold complexion dimm’d;

By chance, or nature’s changing course untrimmed:

Lines from Sonnet XVIII

The S-word (stochastic is a fancy way to say probabilistic) is used to emphasise the headaches of the planner not the operator. Planners don’t tear their hair in panic as operators do, they go bald slowly; Buddhika’s hairless pate shimmers like a polished egg. Look at it in a simple way. Say we have two 100 MW wind farms, one in Mannar, the other Pooneryn. Take Mannar first: Full power output is 100 MW when wind blows with force. Say the mean is 60, hence between zero and 100 it is distributed with a probability like a bell-shaped curve with a peak at 60 and cuts off completely at 100. Pooneryn will be similar but here’s the jinx. The two may not be correlated (occur simultaneously) or only partly correlated. As the apostle John perceptively pointed out, the wind listeth as it wishes.

Northern Territory; expected to yield over 20 TWh

Planner have a good idea how much energy to expect each year from each farm but cannot hope for a steady 120 MW all the time. True they mostly think of the energy availability per annum but they must also tell management to give operators the right tools at each location to ride over severe fluctuations. If there are a large number of wind-farms distributed across the island, planners can estimate how much energy to expect each year or season, but riding through large fluctuations is a different story. I worked on this topic 40 years ago but those braincells are all dead. But don’t panic, there are bright young lads and lasses in CEB planning who know how to tackle these ambiguities.

Operational concerns – the I-word – seem to agitate the CEB these days as more wind farms are slated to come on grid in the next three or four decades (unless the economic debacle of a penniless government shrivels up money for food, medicine, electrification and renewables). The wind that shakes the darling buds of May, and the lovely sun of a summer’s day, are as fickle as my lady’s changing countenance untrimmed. Imagine you are the control engineer leaning back in your dispatcher’s chair sipping your well-earned morning coffee after a busy night reading Tom Mix comic books. You are gloating over 600 MW of wind and solar that you are dispatching, and then the gods strike! A large part of it goes up in metaphorical smoke at a moment’s notice. If wind or solar output fall quickly by a hefty amount, it is the same as the forced outage of a big unit like Victoria or Norochcholai and the shock to the system is similar.

Germany suffers horrendous outages of power whenever the wind gods go on a lightning strike (no pun intended) and the system not only in Germany but throughout the interconnected Northern European grid experiences severe stability problems. Now wind farms are being shredded; see for example:

1. “Thousands of wind turbines in Germany will be shredded next year”

https://www.youtube.com/watch?v=Qr5PEAK1t3U/

2. “Germans fall out of love with wind power” – Financial Times (UK)

https://www.ft.com/content/d8b9b0bc-04a6-11ea-a984-fbbacad9e7dd

3. “The growing mismatch between Germany’s renewables capacity and the strength of its electricity network is leading to curtailment, crazy pricing and challenges for neighbouring nations” greentechmedia.com

Yes of course wind and solar dispatch in the CEB system will never rise to 27% of total capacity as in Germany but the concern does highlight something important. Even if these plants are only 10% to 15% of the total system, operators must be provided with tools to cope with the large swings endemic to I-word generators. I try to make my stuff intelligible to lay readers but am unfairly accused of spewing technical gobbledegook all over. Let me try to simplify how to cope with I-word fluctuations. The response has to be fast, as fast as the wind shakes the darling buds of May. One must act in seconds; firing up gas-turbines or synchronising fast-hydro is not workable, it’s too slow. Two available approaches are a huge amount of excess inertia spinning on the system all the time or massive stand-by battery capacity.

If when driving a heavily laden truck you suffer intermittent petrol blocks, the truck may stutter but it will ride through and keep going thanks to the momentum. In the electricity system it could be heavy generator-rotors delivering little power but spinning along just for a honk. Excess rotating inertia smooths out fluctuations in frequency (comparable to the speed of the truck). There’s a limit to this game; then the fall back is gigantic batteries, fast electronics and inverters (converting battery DC to system AC) when big frequency drops are sensed. This is similar to the uninterrupted power supply (UPS) that backs up a computer when the mains is truant. The problem of course is that a 100 MW UPS needs a battery stack as big as a warehouse and the price tag reaches millions of dollars; comparatively the control-electronics and inverter cost peanuts. If you ever get rich enough to afford a Tesla imagine buying batteries equivalent to those in 1000 Tesla cars to hold hands with a 100 MW wind farm! That’s big money and foreign exchange at that, sitting on the reserve bench just in case one of the eleven blokes on the field breaks a leg. Capital costing of wind power must include the price tag of this ancillary stuff.

I have devoted the column thus far to the stochastic and interruptible nature of wind and solar power. Let me sign off with a few comments on energy; the 70% renewable-source electricity by 2030 fairy story. The economy shrank by 3.6% in 2020 and will do worse in2021; growth will not resume in 2022. The economic meltdown and Foodless Emergency will have knock-on consequences, and electricity growth will decline to below 5%. The government has no dollars to sanction import of food and medicines, so forget about funding big RE expansion! Economy, industry and energy growth may all go belly-up if things go on like this.

The CEB recently said it will need only 28TWh in 2030; seventy percent of this is 19.6TWh. Let me stay with this for the purposes of this column. Major hydro now gives us 3.9TWh but we have pretty much used up all these resources. To round things off let’s say major-hydro can be pushed up to 4.6 TWh by 2030. Wind, solar and mini-hydro will then have to chip in an additional 15 TWh the other half from wind. Speculate then that the prodigies crowding round President Gotabaya expect 7.5 TWh of this to shine from solar. Then these wonks must envision a 10,000-acre Vista of land, replete with say 3.75 GW (3750 MW) of installed solar Splendour. I am rubbing my eyes! And for wind power, I see the Viyathmaga Sancho Panzas advising his Excellency Don Quixote, tilting at windmills.

[In the best locations, a one GW solar array may yield up to 3000 GWh (3 TWh) annually and needs about 3000 acres. Downgrade energy production by a factor of 1.5 and you will get my 3.75 GW RE installed capacity estimate – you can change the derating factor and recalculate. Mother Lanka is blessed with so much rainfall, so many overcast days and such ample passing cloud that “summer’s lease has all too short a day” unlike Atacama, Gobi, Rajasthan or the Australian outback which are pristine for the solar engineer].



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Trade preferences to support post-Ditwah reconstruction

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Ditwah disaster

The manner in which the government succeeded in mobilising support from the international community, immediately after the devastating impact of Cyclone Ditwah, may have surprised many people of this country, particularly because our Opposition politicians were ridiculing our “inexperienced” government, in the recent past, for its inability to deal with the international community effectively. However, by now it is evident that the government, with the assistance of the international community and local nongovernmental actors, like major media organisations, has successfully managed the recovery efforts. So, let me begin by thanking them for what they have done so far.

Yet, some may argue that it is not difficult to mobilise the support for recovery efforts from the international community, immediately after any major disaster, and the real challenge is to sustain that support through the next few weeks, months and years. Because the recovery process, more specifically the post-recovery reconstruction process, requires long-term support. So, the government agencies should start immediately to focus on, in addition to initial disaster relief, a longer-term strategy for reconstruction. This is important because in a few weeks’ time, the focus of the global community may shift elsewhere … to another crisis in another corner of the world. Before that happens, the government should take initiatives to get the support from development partners on appropriate policy measures, including exceptional trade preferences, to help Sri Lanka in the recovery efforts through the medium and the long term.

Use of Trade Preferences to support recovery and reconstruction

In the past, the United States and the European Union used exceptional enhanced trade preferences as part of the assistance packages when countries were devastated by natural disasters, similar to Cyclone Ditwah. For example:

  • After the devastating floods in Pakistan, in July 2010, the EU granted temporary, exceptional trade preferences to Pakistan (autonomous trade preferences) to aid economic recovery. This measure was a de facto waiver on the standard EU GSP (Generalised Scheme of Preferences) rules. The preferences, which were proposed in October 2010 and were applied until the end of 2013, effectively suspended import duties on 75 types of goods, including textiles and apparel items. The available studies on this waiver indicate that though a significant export hike occurred within a few months after the waiver became effective it did not significantly depress exports by competing countries. Subsequently, Pakistan was granted GSP+ status in 2014.

  • Similarly, after the 2015 earthquakes in Nepal, the United States supported Nepal through an extension of unilateral additional preferences, the Nepal Trade Preferences Programme (NTPP). This was a 10-year initiative to grant duty-free access for up to 77 specific Nepali products to aid economic recovery after the 2015 earthquakes. This was also a de facto waiver on the standard US GSP rules.
  • Earlier, after Hurricanes Mitch and Georges caused massive devastation across the Caribbean Basin nations, in 1998, severely impacting their economies, the United States proposed a long-term strategy for rebuilding the region that focused on trade enhancement. This resulted in the establishment of the US Caribbean Basin Trade Partnership Act (CBTPA), which was signed into law on 05 October, 2000, as Title II of the Trade and Development Act of 2000. This was a more comprehensive facility than those which were granted to Pakistan and Nepal.

What type of concession should Sri Lanka request from our development partners?

Given these precedents, it is appropriate for Sri Lanka to seek specific trade concessions from the European Union and the United States.

In the European Union, Sri Lanka already benefits from the GSP+ scheme. Under this arrangement Sri Lanka’s exports (theoretically) receive duty-free access into the EU markets. However, in 2023, Sri Lanka’s preference utilisation rate, that is, the ratio of preferential imports to GSP+ eligible imports, stood at 59%. This was significantly below the average utilisation of other GSP beneficiary countries. For example, in 2023, preference utilisation rates for Bangladesh and Pakistan were 90% and 88%, respectively. The main reason for the low utilisation rate of GSP by Sri Lanka is the very strict Rules of Origin requirements for the apparel exports from Sri Lanka. For example, to get GSP benefits, a woven garment from Sri Lanka must be made from fabric that itself had undergone a transformation from yarn to fabric in Sri Lanka or in another qualifying country. However, a similar garment from Bangladesh only requires a single-stage processing (that is, fabric to garment) qualifies for GSP. As a result, less than half of Sri Lanka’s apparel exports to the EU were ineligible for the preferences in 2023.

Sri Lanka should request a relaxation of this strict rule of origin to help economic recovery. As such a concession only covers GSP Rules of Origin only it would impact multilateral trade rules and would not require WTO approval. Hence could be granted immediately by the EU.

United States

Sri Lanka should submit a request to the United States for (a) temporary suspension of the recently introduced 20% additional ad valorem duty and (b) for a programme similar to the Nepal Trade Preferences Programme (NTPP), but designed specifically for Sri Lanka’s needs. As NTPP didn’t require WTO approval, similar concessions also can be granted without difficulty.

Similarly, country-specific requests should be carefully designed and submitted to Japan and other major trading partners.

(The writer is a retired public servant and can be reached at senadhiragomi@gmail.com)

by Gomi Senadhira

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Lasting power and beauty of words

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Novelists, poets, short story writers, lyricists, politicians and columnists use words for different purposes. While some of them use words to inform and elevate us, others use them to bolster their ego. If there was no such thing called words, we cannot even imagine what will happen to us. Whether you like it or not everything rests on words. If the Penal Code does not define a crime and prescribe a punishment, judges will not be able to convict criminals. Even the Constitution of our country is a printed document.

A mother’s lullaby contains snatches of sweet and healing words. The effect is immediate. The baby falls asleep within seconds. A lover’s soft and alluring words go right into his or her beloved. An army commander’s words encourage soldiers to go forward without fear. The British wartime Prime Minister Winston Churchill’s words still ring in our ears: “… we shall defend our Island, whatever the cost may be, we shall fight on the beaches, we shall fight on the landing grounds, we shall fight in the fields and in the streets, we shall fight in the hills; we shall never surrender …”

Writers wax eloquent on love. English novelist John Galsworthy wrote: “Love is no hot-house flower, but a wild plant, born of a wet night, born of an hour of sunshine; sprung from wild seed, blown along the road by a wild wind. A wild plant that, when it blooms by chance within the hedge of our gardens, we call a flower; and when it blooms outside we call a weed; but flower or weed, whose scent and colour are always wild.” While living in a world dominated by technology, we often hear a bunch of words that is colourless and often cut to verbal ribbons – “How R U” or “Luv U.” Such words seem to squeeze the life out of language.

Changing medium

Language is a constantly changing medium. New words and forms arrive and old ones die out. Whoever thought that the following Sinhala words would find a place in the Oxford English Dictionary? “Asweddumize, Avurudu, Baila, Kiribath, Kottu Roti, Mallung, Osari, Papare, Walawwa and Watalappan.” With all such borrowed words the English language is expanding and remains beautiful. The language helps us to express subtle ideas clearly and convincingly.

You are judged by the words you use. If you constantly use meaningless little phrases, you will be considered a worthless person. When you read a well-written piece of writing you will note how words jump and laugh on the paper or screen. Some of them wag their tails while others stand back like shy village belles. However, they serve a useful purpose. Words help us to write essays, poems, short stories and novels. If not for the beauty of the language, nobody will read what you write.

If you look at the words meaningfully, you will see some of them tap dancing while others stand to rigid attention. Big or small, all the words you pen form part of the action or part of the narrative. The words you write make your writing readable and exciting. That is why we read our favourite authors again and again.

Editorials

If a marriage is to succeed, partners should respect and love each other. Similarly, if you love words, they will help you to use them intelligently and forcefully. A recent survey in the United States has revealed that only eight per cent of people read the editorial. This is because most editorials are not readable. However, there are some editorials which compel us to read them. Some readers collect such editorials to be read later.

Only a lover of words would notice how some words run smoothly without making a noise. Other words appear to be dancing on the floor. Some words of certain writers are soothing while others set your blood pounding. There is a young monk who is preaching using simple words very effectively. He has a large following of young people addicted to drugs. After listening to his preaching, most of them have given up using illegal drugs. The message is loud and clear. If there is no demand for drugs, nobody will smuggle them into the country.

Some politicians use words so rounded at the edges and softened by wear that they are no longer interesting. The sounds they make are meaningless and listeners get more and more confused. Their expressions are full of expletives the meaning of which is often soiled with careless use of words.

Weather-making

Some words, whether written or spoken, stick like superglue. You will never forget them. William Vergara in his short essay on weather-making says, “Cloud-seeding has touched off one of the most baffling controversies in meteorological history. It has been blamed for or credited with practically all kinds of weather. Some scientists claim seeding can produce floods and hail. Others insist it creates droughts and dissipates clouds. Still others staunchly maintain it has no effect at all. The battle is far from over, but at last one clear conclusion is beginning to emerge: man can change the weather, and he is getting better at it.”

There are words that nurse the ego and heal the heart. The following short paragraph is a good example. S. Radhakrishnan says, “In every religion today we have small minorities who see beyond the horizon of their particular faith, not through religious fellowship is possible, not through the imposition of any one way on the whole but through an all-inclusive recognition that we are all searchers for the truth, pilgrims on the road, that we all aim at the same ethical and spiritual standard.”

There are some words joined together in common phrases. They are so beautiful that they elevate the human race. In the phrase ‘beyond a shadow of doubt’, ‘a shadow’ connotes a dark area covering light. ‘A doubt’ refers to hesitancy in belief. We use such phrases blithely because they are exquisitely beautiful in their structure. The English language is a repository of such miracles of expression that lead to deeper understanding or emphasis.

Social media

Social media use words powerfully. Sometimes they invent new words. Through the social media you can reach millions of viewers without the intervention of the government. Their opinion can stop wars and destroy tyrants. If you use the right words, you can even eliminate poverty to a great extent.

The choice of using powerful words is yours. However, before opening your mouth, tap the computer, unclip a pen, write a lyric or poem, think twice of the effect of your writing. When you talk with a purpose or write with pleasure, you enrich listeners and readers with your marvellous language skills. If you have a command of the language, you will put across your point of view that counts. Always try to find the right words and change the world for a better place for us to live.

By R. S. Karunaratne
karunaratners@gmail.com

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Why Sri Lanka Still Has No Doppler Radar – and Who Should Be Held Accountable

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Eighteen Years of Delay:

Cyclone Ditwah has come and gone, leaving a trail of extensive damage to the country’s infrastructure, including buildings, roads, bridges, and 70% of the railway network. Thousands of hectares of farming land have been destroyed. Last but not least, nearly 1,000 people have lost their lives, and more than two million people have been displaced. The visuals uploaded to social media platforms graphically convey the widespread destruction Cyclone Ditwah has caused in our country.

The purpose of my article is to highlight, for the benefit of readers and the general public, how a project to establish a Doppler Weather Radar system, conceived in 2007, remains incomplete after 18 years. Despite multiple governments, shifting national priorities, and repeated natural disasters, the project remains incomplete.

Over the years, the National Audit Office, the Committee on Public Accounts (COPA), and several print and electronic media outlets have highlighted this failure. The last was an excellent five-minute broadcast by Maharaja Television Network on their News First broadcast in October 2024 under a series “What Happened to Sri Lanka”

The Agreement Between the Government of Sri Lanka and the World Meteorological Organisation in 2007.

The first formal attempt to establish a Doppler Radar system dates back to a Trust Fund agreement signed on 24 May 2007 between the Government of Sri Lanka (GoSL) and the World Meteorological Organisation (WMO). This agreement intended to modernize Sri Lanka’s meteorological infrastructure and bring the country on par with global early-warning standards.

The World Meteorological Organisation (WMO) is a specialized agency of the United Nations established on March 23, 1950. There are 193 member countries of the WMO, including Sri Lanka. Its primary role is to promote the establishment of a worldwide meteorological observation system and to serve as the authoritative voice on the state and behaviour of the Earth’s atmosphere, its interaction with the oceans, and the resulting climate and water resources.

According to the 2018 Performance Audit Report compiled by the National Audit Office, the GoSL entered into a trust fund agreement with the WMO to install a Doppler Radar System. The report states that USD 2,884,274 was deposited into the WMO bank account in Geneva, from which the Department of Metrology received USD 95,108 and an additional USD 113,046 in deposit interest. There is no mention as to who actually provided the funds. Based on available information, WMO does not fund projects of this magnitude.

The WMO was responsible for procuring the radar equipment, which it awarded on 18th June 2009 to an American company for USD 1,681,017. According to the audit report, a copy of the purchase contract was not available.

Monitoring the agreement’s implementation was assigned to the Ministry of Disaster Management, a signatory to the trust fund agreement. The audit report details the members of the steering committee appointed by designation to oversee the project. It consisted of personnel from the Ministry of Disaster Management, the Departments of Metrology, National Budget, External Resources and the Disaster Management Centre.

The Audit Report highlights failures in the core responsibilities that can be summarized as follows:

· Procurement irregularities—including flawed tender processes and inadequate technical evaluations.

· Poor site selection

—proposed radar sites did not meet elevation or clearance requirements.

· Civil works delays

—towers were incomplete or structurally unsuitable.

· Equipment left unused

—in some cases for years, exposing sensitive components to deterioration.

· Lack of inter-agency coordination

—between the Meteorology Department, Disaster Management Centre, and line ministries.

Some of the mistakes highlighted are incomprehensible. There is a mention that no soil test was carried out before the commencement of the construction of the tower. This led to construction halting after poor soil conditions were identified, requiring a shift of 10 to 15 meters from the original site. This resulted in further delays and cost overruns.

The equipment supplier had identified that construction work undertaken by a local contractor was not of acceptable quality for housing sensitive electronic equipment. No action had been taken to rectify these deficiencies. The audit report states, “It was observed that the delay in constructing the tower and the lack of proper quality were one of the main reasons for the failure of the project”.

In October 2012, when the supplier commenced installation, the work was soon abandoned after the vehicle carrying the heavy crane required to lift the radar equipment crashed down the mountain. The next attempt was made in October 2013, one year later. Although the equipment was installed, the system could not be operationalised because electronic connectivity was not provided (as stated in the audit report).

In 2015, following a UNOPS (United Nations Office for Project Services) inspection, it was determined that the equipment needed to be returned to the supplier because some sensitive electronic devices had been damaged due to long-term disuse, and a further 1.5 years had elapsed by 2017, when the equipment was finally returned to the supplier. In March 2018, the estimated repair cost was USD 1,095,935, which was deemed excessive, and the project was abandoned.

COPA proceedings

The Committee on Public Accounts (COPA) discussed the radar project on August 10, 2023, and several press reports state that the GOSL incurred a loss of Rs. 78 million due to the project’s failure. This, I believe, is the cost of constructing the Tower. It is mentioned that Rs. 402 million had been spent on the radar system, of which Rs. 323 million was drawn from the trust fund established with WMO. It was also highlighted that approximately Rs. 8 million worth of equipment had been stolen and that the Police and the Bribery and Corruption Commission were investigating the matter.

JICA support and project stagnation

Despite the project’s failure with WMO, the Japan International Cooperation Agency (JICA) entered into an agreement with GOSL on June 30, 2017 to install two Doppler Radar Systems in Puttalam and Pottuvil. JICA has pledged 2.5 billion Japanese yen (LKR 3.4 billion at the time) as a grant. It was envisaged that the project would be completed in 2021.

Once again, the perennial delays that afflict the GOSL and bureaucracy have resulted in the groundbreaking ceremony being held only in December 2024. The delay is attributed to the COVID-19 pandemic and Sri Lanka’s economic crisis.

The seven-year delay between the signing of the agreement and project commencement has led to significant cost increases, forcing JICA to limit the project to installing only one Doppler Radar system in Puttalam.

Impact of the missing radar during Ditwah

As I am not a meteorologist and do not wish to make a judgment on this, I have decided to include the statement issued by JICA after the groundbreaking ceremony on December 24, 2024.

In partnership with the Department of Meteorology (DoM), JICA is spearheading the establishment of the Doppler Weather Radar Network in the Puttalam district, which can realize accurate weather observation and weather prediction based on the collected data by the radar. This initiative is a significant step in strengthening Sri Lanka’s improving its climate resilience including not only reducing risks of floods, landslides, and drought but also agriculture and fishery“.

Based on online research, a Doppler Weather Radar system is designed to observe weather systems in real time. While the technical details are complex, the system essentially provides localized, uptotheminute information on rainfall patterns, storm movements, and approaching severe weather. Countries worldwide rely on such systems to issue timely alerts for monsoons, tropical depressions, and cyclones. It is reported that India has invested in 30 Doppler radar systems, which have helped minimize the loss of life.

Without radar, Sri Lanka must rely primarily on satellite imagery and foreign meteorological centres, which cannot capture the finescale, rapidly changing weather patterns that often cause localized disasters here.

The general consensus is that, while no single system can prevent natural disasters, an operational Doppler Radar almost certainly would have strengthened Sri Lanka’s preparedness and reduced the extent of damage and loss.

Conclusion

Sri Lanka’s inability to commission a Doppler Radar system, despite nearly two decades of attempts, represents one of the most significant governance failures in the country’s disastermanagement history.

Audit findings, parliamentary oversight proceedings, and donor records all confirm the same troubling truth: Sri Lanka has spent public money, signed international agreements, received foreign assistance, and still has no operational radar. This raises a critical question: should those responsible for this prolonged failure be held legally accountable?

Now may not be the time to determine the extent to which the current government and bureaucrats failed the people. I believe an independent commission comprising foreign experts in disaster management from India and Japan should be appointed, maybe in six months, to identify failures in managing Cyclone Ditwah.

However, those who governed the country from 2007 to 2024 should be held accountable for their failures, and legal action should be pursued against the politicians and bureaucrats responsible for disaster management for their failure to implement the 2007 project with the WMO successfully.

Sri Lanka cannot afford another 18 years of delay. The time for action, transparency, and responsibility has arrived.

(The views and opinions expressed in this article are solely those of the author and do not necessarily reflect the policy or position of any organization or institution with which the author is affiliated).

By Sanjeewa Jayaweera

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