What kind of disasters are there

The Disaster Distress Helpline provides immediate crisis counseling to people affected by traumatic events. SAMHSA also has a number of resources for people affected by the Ebola outbreak and incidents of community unrest, including:.

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Skip to main content. Mono Bar U. Main menu. Territories for mental and substance use disorders. Ellos escuchan. They Hear You. Solr Mobile Search. Share Buttons. Disasters therefore can and should be prevented.

We can prevent hazards from leading to disasters by helping communities to be prepared , reduce their risks and become more resilient. These efforts are becoming more and more urgent in the context of the climate crisis. The impacts of global warming are already killing people and devastating lives and livelihoods every year, and they will only get worse without immediate and determined action.

Read more in our latest World Disasters Report. What is a disaster? What are hazards? Natural hazards are naturally occurring physical phenomena. This is primarily the result of improved infrastructure, predicted and response systems to disaster events.

A key metric for assessing hurricane severity is their intensity, and the power they carry. The visualizations here use two metrics to define this: the accumulated cyclone energy ACE , an index that measures the activity of a cyclone season; and the power dissipation index of cyclones.

In the visualization shown we see the global precipitation anomaly each year; trends in the US-specific anomaly can be found here. This precipitation anomaly is measured relative to the century average from to Positive values indicate a wetter year than normal; negative values indicate a drier year.

Also shown is US-specific data on the share of land area which experiences unusually high precipitation in any given year. We can look at precipitation anomalies over the course of year, however, flooding events are often caused by intense rainfall over much shorter periods. Flooding events tend to occur when there is extremely high rainfall over the course of hours or days.

The visualization here shows the extent of extreme one-day precipitation in the US. What we see is a general upwards trend in the extent of extreme rainfall in recent decades. Extreme temperature risks to human health and mortality can result from both exposure to extreme heat and cold.

In the visualizations shown here we see long-term data on heatwaves and unusually high temperatures in the United States. Overall we see there is significant year-to-year variability in the extent of heatwave events. What stands out over the past century of data was the North American heatwave — one of the most extreme heat wave events in modern history, which coincided with the Great Depression and Dust Bowl of the s. Whilst we often focus on heatwave and warm temperatures in relation to weather extremes, extremely low temperatures can often have a high toll on human health and mortality.

In the visualization here we show trends in the share of US land area experiencing unusually low winter temperatures.

In recent years there appears to have been a declining trend in the extent of the US experiencing particularly cold winters. In the charts below we provide three overviews: the number of wildfires, the total acres burned, and the average acres burned per wildfire. This data is shown from onwards, when comparable data recording began. Over the past years we notice three general trends in the charts below although there is significant year-to-year variability :.

The original statistics are available back to the year When we look at this long-term series our chart is here it suggests there has been a significant decline in acres burned over the past century.

However, the NIFC explicitly state:. Prior to , sources of these figures are not known, or cannot be confirmed, and were not derived from the current situation reporting process. As a result the figures prior to should not be compared to later data.

The lack of reliable methods of measurement and reporting mean some historic statistics may in fact be double or triple-counted in national statistics. This means we cannot compare the recent data below with old, historic records. Historically, fires were an often-used method of clearing land for agriculture, for example.

This chart shows the declining death rate due to lightning strikes in the US. In the first decade of the 20th century the average annual rate of deaths was 4. In the first 15 years of the 21st century the death rate had declined to an average of 0.

This is a fold reduction in the likelihood of being killed by lightning in the US. The map here shows the distribution of lightning strikes across the world. This is given as the lightning strike density — the average strikes per square kilometer each year.

In particular we see the high frequency of strikes across the Equatorial regions, especially across central Africa. Natural disasters not only have devastating impacts in terms of the loss of human life, but can also cause severe destruction with economic costs.

When we look at global economic costs over time in absolute terms we tend to see rising costs. But, importantly, the world — and most countries — have also gotten richer. Global gross domestic product has increased more than four-fold since We might therefore expect that for any given disaster, the absolute economic costs could be higher than in the past.

A more appropriate metric to compare economic costs over time is to look at them in relation to GDP. This is the indicator adopted by all countries as part of the UN Sustainable Development Goals to monitor progress on resilience to disaster costs. In the chart shown here we see global direct disaster losses given as a share of GDP.

There is notable year-to-year variability in costs — ranging from 0. In recent decades there has been no clear trending increase in damages when we take account of economic growth over this period.

This is also true when we look at damages specifically for weather-related disasters. This trend in damages relative to global GDP is also shown in the interactive chart. Since economic losses from disasters in relation to GDP is the indicator adopted by all countries within the UN Sustainable Development Goals, this data is also now reported for each country.

The map shows direct disaster costs for each country as a share of its GDP. Here we see large variations by country — a fold difference ranging from less than 0. This data can be found in absolute terms here. The two authors found that for every person killed by a volcano, nearly 40, people have to die of a food shortage to get the same probability of coverage in US televised news. In other words, the type of disaster matters to how newsworthy networks find it to be. The findings tells us, among other important things, that networks tend to be selective in their coverage and attention is not reflecting the severity and number of people killed or affected by a natural disaster.

Food shortages , for example, result in the most casualties and affect the most people per incident 13 but their onset is more gradual than that of a volcanic explosion or sudden earthquake. This bias for the spectacular is not only unfair and misleading, but also has the potential to misallocate attention and aid.

Disasters that happen in an instant leave little time for preventative intervention. On the other hand, the gradual disasters that tend to affect more lives build up slowly, allowing more time for preventative measures to be taken. However, in a Catch situation, the gradual nature of these calamities is also what prevents them from garnering the media attention they deserve. There are other biases, too. However, after controlling for disaster type, along with other factors such as the number killed and the timing of the news, there is no significant difference between coverage of African and Asian disasters.

Instead, a huge difference emerges between coverage of Africa, Asia, and the Pacific on the one hand, and Europe and South and Central America, on the other. The two visualizations show the extent of this bias. One of the major successes over the past century has been the dramatic decline in global deaths from natural disasters — this is despite the fact that the human population has increased rapidly over this period. Behind this improvement has been the improvement in living standards; access to and development of resilient infrastructure; and effective response systems.

These factors have been driven by an increase in incomes across the world. What remains true today is that populations in low-income countries — those where a large percentage of the population still live in extreme poverty , or score low on the Human Development Index — are more vulnerable to the effects of natural disasters.

We see this effect in the visualization shown. This chart shows the death rates from natural disasters — the number of deaths per , population — of countries grouped by their socio-demographic index SDI. What we see is that the large spikes in death rates occur almost exclusively for countries with a low or low-middle SDI. Highly developed countries are much more resilient to disaster events and therefore have a consistently low death rate from natural disasters.

Note that this does not mean low-income countries have high death tolls from disasters year-to-year: the data here shows that in most years they also have very low death rates.

But when low-frequency, high-impact events do occur they are particularly vulnerable to its effects. Overall development, poverty alleviation, and knowledge-sharing of how to increase resilience to natural disasters will therefore be key to reducing the toll of disasters in the decades to come. There are multiple terms used to describe extreme weather events: hurricanes, typhoons, cyclones and tornadoes.

What is the difference between these terms, and how are they defined? The terms hurricane , cyclone and typhoon all refer to the same thing; they can be used interchangeably. A tropical cyclone is a weather event which originates over tropical or subtropical waters and results in a rotating, organized system of clouds and thunderstorms.

Its circulation patterns should be closed and low-level. The choice of terminology is location-specific and depends on where the storm originates. The term hurricane is used to describe a tropical cyclone which originates in the North Atlantic, central North Pacific, and eastern North Pacific.

When it originates in the Northwest Pacific, we call it typhoon. In the South Pacific and Indian Ocean the general term tropical cyclone is used. In other words, the only difference between a hurricane and typhoon is where it occurs. The characteristics of a hurricane are described in detail at the NASA website. A tropical disturbance arises over warm ocean waters. It can grow into a tropical depression which is an area of rotating thunderstorms with winds up to 62 kilometres 38 miles per hour.

Whilst hurricanes and tornadoes have a characteristic circulatory wind patterns, they are very different weather systems. The main difference between the systems is scale tornadoes are small-scale circulatory systems; hurricanes are large-scale. These differences are highlighted in the table below:. The VEI is derived based on the erupted mass or deposit of an eruption. Historic eruptions that were definitely explosive, but carry no other descriptive information are assigned a default VEI of 2.

A key issue of data quality is the consistency of even reporting over time. For long-term trends in natural disaster events we know that reporting and recording of events today is much more advanced and complete than in the past.

This can lead to significant underreporting or uncertainty of events in the distant past.