Storm surges, one-off events associated with storms that can cause flooding, are rare and highly destructive phenomena. A paper published this week in Nature finds that they have increased since 1960, comparable to the increase in average sea level rise over the same period.

The authors, led by Spaniard Francisco Calafat of the National Oceanography Centre in Liverpool, UK, statistically analyse observations of extreme tides from 79 tide gauges on European coasts over the period 1960-2018, and compare them with climate models.

Their results point to an increase in extreme sea levels in the future, something the authors say has implications for coastal planning. So far, the most widely accepted hypothesis is that the frequency of such extreme storm surges would not increase.

The weekend saw record temperatures in both the Arctic and Antarctica, up to 40°C above normal for this time of year.

The Public Health Commission has updated the Covid-19 Surveillance and Control Strategy, which will come into force on Monday 28 March. From then on, as long as indicators of healthcare utilisation are at low risk, diagnostic testing will focus on vulnerable individuals and settings and severe cases. Surveillance will focus on these groups.

Japan's IBUKI greenhouse gas observation satellites (GOSAT) have just announced the detection of a sharp annual increase in the average atmospheric methane concentration in 2021, the largest since 2011. European (ESA) and US (NASA) space agencies, as well as ground stations, have also detected spikes.

Several results confirm that vaccination against covid-19 does not affect fertility. One of them, carried out on some 2,000 couples and published in the American Journal of Epidemiology, compares the ability to conceive naturally in vaccinated and unvaccinated couples. The other, in Obstetrics & Gynecology, studies some 1,300 vaccinated and unvaccinated women who have used different assisted reproductive techniques. Neither paper finds a link between vaccination and pregnancy.

Spain recommends that people who have been infected with the coronavirus receive the third dose four weeks later. Experts assess the decision from an immunological point of view.

The director of the Vaccine Strategy of the European Medicines Agency (EMA), Marco Cavaleri, told a press conference on 11 January that "it is not sustainable in the long term to continue giving booster doses every three or four months [to the general population]". Spanish immunologists agree that this is not the right thing to do. In these reactions they explain why.

In recent days, several countries have modified the quarantine times for close contacts and the isolation of infected people, while others are already considering it. Spain has announced that it will reduce these periods to 7 days, both for people who have tested positive in a test and for close contacts who require quarantine (in the case of our country, unvaccinated people).

La EMA ha recomendado hoy la autorización de la quinta vacuna frente a la covid-19 para mayores de 18 años: la estadounidense Novavax, la primera basada en una plataforma de proteínas recombinantes.