La Niña returns and leaves the next coffee harvest uncertain

In the last month, rains occurred in much of Brazil. From Rio Grande do Sul to Mato Grosso do Sul and São Paulo, the rain occurred more irregularly and moderately. However, as expected, in a large part of the central region of Brazil, in an area involving the south of Pará, the states of Mato Grosso and Espírito Santo and the southern part of Maranhão, the volume of rain occurred more regularly and a little above average. In this region, temperatures were milder, while in the southern region of Brazil, some locations had temperatures above the expected average for the month.

The ENSO phenomenon

In October, the trade winds were stronger than normal and there was also a continued reduction in temperatures in the Equatorial Pacific. Due to these prevailing atmospheric and oceanic conditions, among others, the La Niña phenomenon was confirmed, which, according to some climate models, is expected to remain until next autumn.

In Figure 1 it is possible to observe the expansion of the anomalous cooling (marked in blue under the purple line) in which temperatures below average, mainly between 140-120ºW, presented approximately the same thermal amplitude as the previous month.

The current La Niña phenomenon could affect temperature and rainfall over the next few months, similar to what occurred at the end of last year. However, at the moment, the intensity of the current La Niña is lower than the last event that occurred.

Rains in the coming months

December

In Figure 2 it can be seen that the greater the intensity of the green color, the greater the probability of rainfall occurring above average in the month of December. The area highlighted in light blue, delimited by the purple line, is the one where there is a greater probability of rainfall occurring above the average for the month. On the other hand, the greater the intensity of yellow, the greater the probability of below-average rainfall.

January 2022

The greatest probability of above-average rainfall this month is expected for the mesoregions of greater Florianópolis, Vale do Itajaí, North and South Santa Catarina. The same could be repeated in the metropolitan mesoregion of Curitiba, Central Oriental, North Central, North Pioneiro and Southeast of Paraná, and in São Paulo, in the mesoregions of Itapetininga, Assis and Marília.

In the Northeast region of Brazil, the volume of rainfall may occur slightly above average in Rio Grande do Norte, Paraíba and Pernambuco, with the exception of the extreme south of the Sertão Pernambucano. This forecast is also repeated for Sergipe and Ceará, with the exception of the Sertões Cearenses, up to the mesoregions of the Northeast and Central North of Bahia.

In Goiás, Tocantins, Rio de Janeiro, Espírito Santo, Mato Grosso do Sul and Minas Gerais, rainfall is expected to occur within the period average. However, the mesoregion of Northern Minas may experience below-average rainfall this month.

February 2022

This month, due to the presence of La Niña, there is greater uncertainty regarding the region that will most likely record below-average rainfall. This probability is expected for Rio Grande do Sul, with the exception of the Northeast and Northwest Rio Grande do Sul mesoregions; for the Federal District, North and East of Goiano; Far West of Bahia and for the North and Northwest mesoregions of Minas, Jequitinhonha and the Mucuri and Rio Doce Valleys, and also for the Northwest and North Coast of Espírito Santo.

The states of Paraná, São Paulo, Mato Grosso do Sul and the mesoregion of Southern Minas may experience rainfall at or slightly above average this month.

Temperatures in the coming months

During periods of La Niña, the temperature tends to be milder in the summer in the Southeast and Central-West regions. In the current La Niña event, it is expected that in the months of December and January, milder temperatures will occur more in the Northeast and North regions of Brazil, from the Far West of Bahia, through Piauí, Maranhão and arriving in Pará. In the states of Mato Grosso do Sul and in Rio Grande do Sul temperatures can be within or slightly above the average for the months.

In February, average temperatures are expected for almost all of Brazil, with the exception of Pará and Amapa, where temperatures may be milder.

The next few weeks

It is expected that by the end of November the greatest volume of rain will be concentrated in the extreme south of Pará, passing through Mato Grosso, Tocantins, Goiás, Distrito Federal, Sul Maranhense, Extreme West, Central South Bahia. In addition, the forecast is repeated to the North, Jequitinhonha, Vale do Rio Doce and the Metropolitan region of Belo Horizonte, in Minas Gerais.

Café

With the high rainfall, which occurred from the beginning of October in the coffee region and the probability of rains occurring above average at the beginning of summer, many producers have already started cultural treatments to recover the vegetative development of crops that had high defoliation, as well as for the recovery of the nutritional status of plants.

Fertilizations and sprays to replace the removed nutrients have been carried out based on the results of soil analysis that were collected after harvest, and the next fertilizations and sprays must also be based on foliar analysis, which should be carried out in December, when the fruits are at the chumbinho stage. This care for crops has been discouraged by the high prices of inputs, in addition to the fact that many have been, and are still being, pruned due to the depletion seen after the last harvest and the abortion of flowers and seeds.

This year, after the start of the rains, there were exuberant flowerings in the coffee plantations, but very low pellet capture has been observed. During the pre-flowering period, there was a period of prolonged drought, excessive heat, occurrence of frost, thermal inversion and attacks by pests and diseases, which contributed to the high defoliation of plants, affecting the development of reproductive structures. In the current harvest, it has also been observed, in crops in the coffee growing regions of Minas, that buds that should be reproductive have become vegetative, showing high secondary branches in the plagiotropic branches (Figure 3).

Given the current scenario, considering the low flowering rate and the high drop rate of pellets, producers are concerned about the size of the next harvest.

Prognosis

The climate analyzes and forecasts presented here were prepared based on statistics and histories of the occurrence of global climate phenomena, mainly those active in South America. Information made freely available by NOAA was also considered; by the International Institute for Research on Climate and Society — IRI; by the Met Office Hadley Centre; by the European Center for Medium-Range Weather Forecasts — ECMWF; by the Amazon Climate Bulletin prepared by the Meteorology Division (Divmet) of the Amazon Protection System (Sipam) and based on climate data made available by INMET. (5th Disme) / CPTEC-Inpe.

The climate forecast refers to natural phenomena that have chaotic characteristics and are subject to drastic changes. Therefore, EPAMIG and Embrapa Café are not responsible for any damage or loss that the reader may suffer, or may cause to third parties, due to the improper use of the information contained in the text. Therefore, it is the reader's sole responsibility to use the information provided here.